Basic Math Examples

Solve for r (r-3)(r+9)=12
Step 1
Simplify .
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Step 1.1
Expand using the FOIL Method.
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Step 1.1.1
Apply the distributive property.
Step 1.1.2
Apply the distributive property.
Step 1.1.3
Apply the distributive property.
Step 1.2
Simplify and combine like terms.
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Step 1.2.1
Simplify each term.
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Step 1.2.1.1
Multiply by .
Step 1.2.1.2
Move to the left of .
Step 1.2.1.3
Multiply by .
Step 1.2.2
Subtract from .
Step 2
Move all terms to the left side of the equation and simplify.
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Step 2.1
Subtract from both sides of the equation.
Step 2.2
Subtract from .
Step 3
Use the quadratic formula to find the solutions.
Step 4
Substitute the values , , and into the quadratic formula and solve for .
Step 5
Simplify.
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Step 5.1
Simplify the numerator.
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Step 5.1.1
Raise to the power of .
Step 5.1.2
Multiply .
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Step 5.1.2.1
Multiply by .
Step 5.1.2.2
Multiply by .
Step 5.1.3
Add and .
Step 5.1.4
Rewrite as .
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Step 5.1.4.1
Factor out of .
Step 5.1.4.2
Rewrite as .
Step 5.1.5
Pull terms out from under the radical.
Step 5.2
Multiply by .
Step 5.3
Simplify .
Step 6
The final answer is the combination of both solutions.
Step 7
The result can be shown in multiple forms.
Exact Form:
Decimal Form: