Question

if the difference of two numbers is equal to the half of the sum of these two number . if first number is equal to the dual of second number +5. then find both numbers.

Answer 1

Let
the numbers be x and y
according to the first condition
x-y=1/2(x+y). equ 1
according to second condition
x=2y+5. equ 2
put equation 2 in equation 1
2y+5-y=1/2(2y+5+y)
2y+10=3y+5
3y-2y=10-5
y=5
put y=5 in equation 2
2y+5
2×5+5
10+5
15