Solve the system of equations by the method of substitution

Solve the system of equations by the method of substitution.

20) y = -2x

-6x - 5 y = -8

Solution

y = -2x

-6x - 5y = -8

substituting the value of y from equation 1 into equation 2

- 6x - 5(-2x) = - 8

-6x + 10x = -8

4x = -8

dividing both sides by 4

x = - 2

plugging x = -2 in equation 1

y = -2 (-2)

y = 4

solution is x = - 2

y = 4