Question

What is the solution of the system equation?
y=3x+7
y=x-9

Answer 1

y=-17, x=-8

Explanation:

x-9=3x+7

Isolate x for x-9=3x+7;

x-9=3x+7

Add 9 to both sides:

x-9+9=3x+7+9

Simplify;

x=3x+16

Subtract 3x from both sides;

x-3x=3x+16-3x

Simplify;

-2x=16

Divide both sides by -2;

-2x/-2=16/-2

simplify: -2x/-2

=x

Simplify 16/-2:

x=-8

For y=x-9 substitute x=-8;

y=-8-9

Simplify;

y=-17

The solutions to the System of equations are;

y=-17, x=-8