Question

The sum of two numbers is 15 and the difference is 4. Let the two numbers be x and y.

Write down a pair of simultaneous equations involving x and y. Solve the equations.

Answer 1

x=9.5 and y=5.5

Explanation:

x+y=15

x-y=4

add

2x=19

x=9.5

y=15-9.5

y=5.5

x=9.5 and y=5.5