Question

solve the system of equations : what is the x - value for the solution ? 2x + 7y =3 and x = 1 - 4y A. -1 B. 5 C. 4 D. 3 ?

Answer 1

2x+7y -(1)
x= 1-4y -(2)

Sub (2) into (1): 2(1-4y) + 7y = 3
2-8y+7y = 3
-y= 1
y= -1

Hence sub y=-1 into (2):
x= 1-4(-1)
x=5

Ans: B