Answer: x = 2 and y = 1
Step-by-step explanation: What we have here is a pair of simultaneous equations and we have been instructed to solve by using the substitution method.
The equations are
y = 2x - 3 ------(1)
y = -8x + 17 ----(2)
The y variable has a coefficient of 1 in both equations so we can start with either of equation (1) or (2).
From equation (1) y = 2x - 3. Substitute for the value of y into equation (2)
2x - 3 = -8x + 17
By collecting like terms we now have
2x + 8x = 17 + 3
(Remember that when a negative value crosses to the other side of the equation it becomes positive and vice versa)
10x = 20
Divide both sides of the equation by 10
x = 2
Having calculated the value of x, we can now substitute for the value of x into equation (1)
y = 2x - 3
y = 2(2) - 3
y = 4 - 3
y = 1
Therefore, x = 2 and y = 1.
