Answer: (-2, 11) That is, x = -2 and y = 11
Step-by-step explanation: We have a pair of simultaneous equations and since none of the variables has a coefficient of 1, we shall solve by use of the elimination method. The equations are
7x + 2y = 8 ———(1)
-5x - 2y = -12 ——(2)
The coefficients of the y variable in both equations is 2 in either case. So straight away, we add both equations together. (This is because of the negative sign in one the coefficients of y).
Adding both equations results in;
(7x + -5x) +(2y + -2y) = (8 + -12)
2x = -4
Divide both sides of the equation by 2
x = -2
Having calculated x, we now substitute for the value of x into equation (1)
7x + 2y = 8
7(-2) + 2y = 8
-14 + 2y = 8
Add 14 to both sides of the equation
2y = 22
Divide both sides of the equation by 2
y = 11
Therefore, x = -2 and y = 11
