Solve the following simultaneous equation for x. x2 + y - 5 = 0, y - 7x + 3 = 0
A
-2, 4
B
2, 4
C
-1,8
D
1, -8
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
x2 + y - 5 = 0.....(i)
y - 7x + 3 = 0.........(ii)
y = 7x - 3, substituting the value of y in equation (i)
x2 + (7x - 3) - 5 = 0
x2 + 7x + 3 = 0
(x + 8)(x - 1) = 0
x = -8 or 1
Source: Myschool Past Questions Archive (Record #31173)