Precalculus Examples
x+y=0x+y=0 , x-y=0x−y=0
Step 1
Step 1.1
Multiply each equation by the value that makes the coefficients of xx opposite.
x+y=0x+y=0
(-1)⋅(x-y)=(-1)(0)(−1)⋅(x−y)=(−1)(0)
Step 1.2
Simplify.
Step 1.2.1
Simplify the left side.
Step 1.2.1.1
Simplify (-1)⋅(x-y)(−1)⋅(x−y).
Step 1.2.1.1.1
Apply the distributive property.
x+y=0x+y=0
-1x-1(-y)=(-1)(0)−1x−1(−y)=(−1)(0)
Step 1.2.1.1.2
Rewrite -1x−1x as -x−x.
x+y=0x+y=0
-x-1(-y)=(-1)(0)−x−1(−y)=(−1)(0)
Step 1.2.1.1.3
Multiply -1(-y)−1(−y).
Step 1.2.1.1.3.1
Multiply -1−1 by -1−1.
x+y=0x+y=0
-x+1y=(-1)(0)−x+1y=(−1)(0)
Step 1.2.1.1.3.2
Multiply yy by 11.
x+y=0x+y=0
-x+y=(-1)(0)−x+y=(−1)(0)
x+y=0x+y=0
-x+y=(-1)(0)−x+y=(−1)(0)
x+y=0x+y=0
-x+y=(-1)(0)−x+y=(−1)(0)
x+y=0x+y=0
-x+y=(-1)(0)−x+y=(−1)(0)
Step 1.2.2
Simplify the right side.
Step 1.2.2.1
Multiply -1−1 by 00.
x+y=0x+y=0
-x+y=0−x+y=0
x+y=0x+y=0
-x+y=0−x+y=0
x+y=0x+y=0
-x+y=0−x+y=0
Step 1.3
Add the two equations together to eliminate xx from the system.
xx | ++ | yy | == | 00 | ||||
++ | -− | xx | ++ | yy | == | 00 | ||
22 | yy | == | 00 |
Step 1.4
Divide each term in 2y=02y=0 by 22 and simplify.
Step 1.4.1
Divide each term in 2y=02y=0 by 22.
2y2=022y2=02
Step 1.4.2
Simplify the left side.
Step 1.4.2.1
Cancel the common factor of 22.
Step 1.4.2.1.1
Cancel the common factor.
2y2=02
Step 1.4.2.1.2
Divide y by 1.
y=02
y=02
y=02
Step 1.4.3
Simplify the right side.
Step 1.4.3.1
Divide 0 by 2.
y=0
y=0
y=0
Step 1.5
Substitute the value found for y into one of the original equations, then solve for x.
Step 1.5.1
Substitute the value found for y into one of the original equations to solve for x.
x+0=0
Step 1.5.2
Add x and 0.
x=0
x=0
Step 1.6
The solution to the independent system of equations can be represented as a point.
(0,0)
(0,0)
Step 2
Since the system has a point of intersection, the system is independent.
Independent
Step 3