Precalculus Examples

Solve by Substitution x^2+y^2=16 , 4x+7y=13
,
Step 1
Solve for in .
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Step 1.1
Subtract from both sides of the equation.
Step 1.2
Divide each term in by and simplify.
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Step 1.2.1
Divide each term in by .
Step 1.2.2
Simplify the left side.
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Step 1.2.2.1
Cancel the common factor of .
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Step 1.2.2.1.1
Cancel the common factor.
Step 1.2.2.1.2
Divide by .
Step 1.2.3
Simplify the right side.
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Step 1.2.3.1
Move the negative in front of the fraction.
Step 2
Replace all occurrences of with in each equation.
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Step 2.1
Replace all occurrences of in with .
Step 2.2
Simplify the left side.
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Step 2.2.1
Simplify .
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Step 2.2.1.1
Simplify each term.
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Step 2.2.1.1.1
Rewrite as .
Step 2.2.1.1.2
Expand using the FOIL Method.
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Step 2.2.1.1.2.1
Apply the distributive property.
Step 2.2.1.1.2.2
Apply the distributive property.
Step 2.2.1.1.2.3
Apply the distributive property.
Step 2.2.1.1.3
Simplify and combine like terms.
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Step 2.2.1.1.3.1
Simplify each term.
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Step 2.2.1.1.3.1.1
Multiply .
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Step 2.2.1.1.3.1.1.1
Multiply by .
Step 2.2.1.1.3.1.1.2
Multiply by .
Step 2.2.1.1.3.1.1.3
Multiply by .
Step 2.2.1.1.3.1.2
Multiply .
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Step 2.2.1.1.3.1.2.1
Multiply by .
Step 2.2.1.1.3.1.2.2
Multiply by .
Step 2.2.1.1.3.1.2.3
Multiply by .
Step 2.2.1.1.3.1.3
Multiply .
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Step 2.2.1.1.3.1.3.1
Multiply by .
Step 2.2.1.1.3.1.3.2
Multiply by .
Step 2.2.1.1.3.1.3.3
Multiply by .
Step 2.2.1.1.3.1.4
Multiply .
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Step 2.2.1.1.3.1.4.1
Multiply by .
Step 2.2.1.1.3.1.4.2
Multiply by .
Step 2.2.1.1.3.1.4.3
Multiply by .
Step 2.2.1.1.3.1.4.4
Multiply by .
Step 2.2.1.1.3.1.4.5
Raise to the power of .
Step 2.2.1.1.3.1.4.6
Raise to the power of .
Step 2.2.1.1.3.1.4.7
Use the power rule to combine exponents.
Step 2.2.1.1.3.1.4.8
Add and .
Step 2.2.1.1.3.1.4.9
Multiply by .
Step 2.2.1.1.3.2
Subtract from .
Step 2.2.1.1.4
Simplify each term.
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Step 2.2.1.1.4.1
Cancel the common factor of .
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Step 2.2.1.1.4.1.1
Factor out of .
Step 2.2.1.1.4.1.2
Factor out of .
Step 2.2.1.1.4.1.3
Cancel the common factor.
Step 2.2.1.1.4.1.4
Rewrite the expression.
Step 2.2.1.1.4.2
Rewrite as .
Step 2.2.1.2
To write as a fraction with a common denominator, multiply by .
Step 2.2.1.3
Simplify terms.
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Step 2.2.1.3.1
Combine and .
Step 2.2.1.3.2
Combine the numerators over the common denominator.
Step 2.2.1.3.3
Combine the numerators over the common denominator.
Step 2.2.1.4
Move to the left of .
Step 2.2.1.5
Add and .
Step 2.2.1.6
Simplify each term.
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Step 2.2.1.6.1
Factor out of .
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Step 2.2.1.6.1.1
Factor out of .
Step 2.2.1.6.1.2
Factor out of .
Step 2.2.1.6.1.3
Factor out of .
Step 2.2.1.6.2
Move the negative in front of the fraction.
Step 2.2.1.7
To write as a fraction with a common denominator, multiply by .
Step 2.2.1.8
Write each expression with a common denominator of , by multiplying each by an appropriate factor of .
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Step 2.2.1.8.1
Multiply by .
Step 2.2.1.8.2
Multiply by .
Step 2.2.1.9
Combine the numerators over the common denominator.
Step 2.2.1.10
Simplify the numerator.
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Step 2.2.1.10.1
Factor out of .
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Step 2.2.1.10.1.1
Factor out of .
Step 2.2.1.10.1.2
Factor out of .
Step 2.2.1.10.2
Multiply by .
Step 2.2.1.10.3
Reorder terms.
Step 3
Solve for in .
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Step 3.1
Multiply both sides by .
Step 3.2
Simplify.
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Step 3.2.1
Simplify the left side.
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Step 3.2.1.1
Simplify .
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Step 3.2.1.1.1
Cancel the common factor of .
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Step 3.2.1.1.1.1
Cancel the common factor.
Step 3.2.1.1.1.2
Rewrite the expression.
Step 3.2.1.1.2
Apply the distributive property.
Step 3.2.1.1.3
Simplify.
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Step 3.2.1.1.3.1
Multiply by .
Step 3.2.1.1.3.2
Multiply by .
Step 3.2.1.1.3.3
Multiply by .
Step 3.2.2
Simplify the right side.
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Step 3.2.2.1
Multiply by .
Step 3.3
Solve for .
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Step 3.3.1
Move all terms to the left side of the equation and simplify.
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Step 3.3.1.1
Subtract from both sides of the equation.
Step 3.3.1.2
Subtract from .
Step 3.3.2
Use the quadratic formula to find the solutions.
Step 3.3.3
Substitute the values , , and into the quadratic formula and solve for .
Step 3.3.4
Simplify.
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Step 3.3.4.1
Simplify the numerator.
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Step 3.3.4.1.1
Raise to the power of .
Step 3.3.4.1.2
Multiply .
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Step 3.3.4.1.2.1
Multiply by .
Step 3.3.4.1.2.2
Multiply by .
Step 3.3.4.1.3
Add and .
Step 3.3.4.1.4
Rewrite as .
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Step 3.3.4.1.4.1
Factor out of .
Step 3.3.4.1.4.2
Rewrite as .
Step 3.3.4.1.5
Pull terms out from under the radical.
Step 3.3.4.2
Multiply by .
Step 3.3.4.3
Simplify .
Step 3.3.5
Simplify the expression to solve for the portion of the .
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Step 3.3.5.1
Simplify the numerator.
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Step 3.3.5.1.1
Raise to the power of .
Step 3.3.5.1.2
Multiply .
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Step 3.3.5.1.2.1
Multiply by .
Step 3.3.5.1.2.2
Multiply by .
Step 3.3.5.1.3
Add and .
Step 3.3.5.1.4
Rewrite as .
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Step 3.3.5.1.4.1
Factor out of .
Step 3.3.5.1.4.2
Rewrite as .
Step 3.3.5.1.5
Pull terms out from under the radical.
Step 3.3.5.2
Multiply by .
Step 3.3.5.3
Simplify .
Step 3.3.5.4
Change the to .
Step 3.3.6
Simplify the expression to solve for the portion of the .
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Step 3.3.6.1
Simplify the numerator.
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Step 3.3.6.1.1
Raise to the power of .
Step 3.3.6.1.2
Multiply .
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Step 3.3.6.1.2.1
Multiply by .
Step 3.3.6.1.2.2
Multiply by .
Step 3.3.6.1.3
Add and .
Step 3.3.6.1.4
Rewrite as .
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Step 3.3.6.1.4.1
Factor out of .
Step 3.3.6.1.4.2
Rewrite as .
Step 3.3.6.1.5
Pull terms out from under the radical.
Step 3.3.6.2
Multiply by .
Step 3.3.6.3
Simplify .
Step 3.3.6.4
Change the to .
Step 3.3.7
The final answer is the combination of both solutions.
Step 4
Replace all occurrences of with in each equation.
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Step 4.1
Replace all occurrences of in with .
Step 4.2
Simplify the right side.
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Step 4.2.1
Simplify .
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Step 4.2.1.1
Combine the numerators over the common denominator.
Step 4.2.1.2
Simplify each term.
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Step 4.2.1.2.1
Combine and .
Step 4.2.1.2.2
Move the negative in front of the fraction.
Step 4.2.1.3
To write as a fraction with a common denominator, multiply by .
Step 4.2.1.4
Combine fractions.
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Step 4.2.1.4.1
Combine and .
Step 4.2.1.4.2
Combine the numerators over the common denominator.
Step 4.2.1.5
Simplify the numerator.
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Step 4.2.1.5.1
Multiply by .
Step 4.2.1.5.2
Apply the distributive property.
Step 4.2.1.5.3
Multiply by .
Step 4.2.1.5.4
Multiply by .
Step 4.2.1.5.5
Subtract from .
Step 4.2.1.6
Multiply the numerator by the reciprocal of the denominator.
Step 4.2.1.7
Multiply .
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Step 4.2.1.7.1
Multiply by .
Step 4.2.1.7.2
Multiply by .
Step 4.2.1.8
Cancel the common factor of and .
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Step 4.2.1.8.1
Factor out of .
Step 4.2.1.8.2
Factor out of .
Step 4.2.1.8.3
Factor out of .
Step 4.2.1.8.4
Cancel the common factors.
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Step 4.2.1.8.4.1
Factor out of .
Step 4.2.1.8.4.2
Cancel the common factor.
Step 4.2.1.8.4.3
Rewrite the expression.
Step 5
Replace all occurrences of with in each equation.
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Step 5.1
Replace all occurrences of in with .
Step 5.2
Simplify the right side.
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Step 5.2.1
Simplify .
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Step 5.2.1.1
Combine the numerators over the common denominator.
Step 5.2.1.2
Simplify each term.
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Step 5.2.1.2.1
Combine and .
Step 5.2.1.2.2
Move the negative in front of the fraction.
Step 5.2.1.3
To write as a fraction with a common denominator, multiply by .
Step 5.2.1.4
Combine fractions.
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Step 5.2.1.4.1
Combine and .
Step 5.2.1.4.2
Combine the numerators over the common denominator.
Step 5.2.1.5
Simplify the numerator.
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Step 5.2.1.5.1
Multiply by .
Step 5.2.1.5.2
Apply the distributive property.
Step 5.2.1.5.3
Multiply by .
Step 5.2.1.5.4
Multiply by .
Step 5.2.1.5.5
Subtract from .
Step 5.2.1.6
Multiply the numerator by the reciprocal of the denominator.
Step 5.2.1.7
Multiply .
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Step 5.2.1.7.1
Multiply by .
Step 5.2.1.7.2
Multiply by .
Step 5.2.1.8
Cancel the common factor of and .
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Step 5.2.1.8.1
Factor out of .
Step 5.2.1.8.2
Factor out of .
Step 5.2.1.8.3
Factor out of .
Step 5.2.1.8.4
Cancel the common factors.
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Step 5.2.1.8.4.1
Factor out of .
Step 5.2.1.8.4.2
Cancel the common factor.
Step 5.2.1.8.4.3
Rewrite the expression.
Step 6
The solution to the system is the complete set of ordered pairs that are valid solutions.
Step 7
The result can be shown in multiple forms.
Point Form:
Equation Form:
Step 8