Process of substitution
y=6x+24
y=-2x-16

(-5, -6) That is, x = -5 and y = -6

Step-by-step explanation: The pair of simultaneous equations are given as follows

y = 6x + 24 ———(1)

y = -2x - 16 ———(2)

The instruction is to use the substitution method, hence

Substitute for the value of y = -2x - 16 into equation (1)

-2x - 16 = 6x + 24

By collecting like terms we now have

-2x - 6x = 24 + 16

Remember when a negative value crosses to the other side of the equation it becomes positive and vice versa

-8x = 40

Divide both sides of the equation by -8

x = -5

Having found the value of x, substitute for the value of x into equation (2)

y = -2(-5) - 16

y = 10 - 16

y = -6

Therefore x = -5 and y = -6