Question

Solve the system of equations.

y = x2 + 4
y = 5x

Answer 1

y = x^2 + 4 . . . . . (1)
y = 5x . . . . . . . . .(2)

Putting (2) into (1) gives, 5x = x^2 + 4
x^2 - 5x + 4 = 0
(x - 1)(x - 4) = 0
x = 1 and x = 4
y = 5(1) and y = 5(4)
y = 5 and y = 20

Therefore solutions are: (1, 5) and (4, 20)