Question

Solve the simultaneous equations.

You must show all your working.

x-y=7
x² + y = 149

Answer 1

x = 12, y = 5

x = -13, y = -20

Step by step explanation:

You have two equations, and you have to find a way to merge them.

x - y = 7 —— {1}

From {1}, y = x - 7 —— {2}

x² + y = 149 —— {3}

Rep {2} in {3}

x² + y = 149

x² + (x-7) = 149

x² + x - 156 = 0

(x-12) (x+13) = 0

x = 12 and x = - 13

When x = 12, y = 12 - 7 = 5

(12, 5)

When x = - 13, y = - 13 - 7 = - 20

(-13, - 20)