Question

The sum of two numbers is 12. The difference of the same two numbers is -4

Answer 1

Let the two numbers are x and y

Sum of two numbers = 12

x + y = 12 ---------- equation 1

Difference of two numbers = - 4

x - y = - 4 ---------- equation 2

Equation 1. + Equation 2

x + y = 12 ----------eq.1

x - y = - 4 ---------eq.2

___________________

x + x = 12 - 4

2x = 8

x = 8/2

x = 4

Substitute x = 4 in eq 1

4 + y = 12

y = 12/4

y = 3