Question

Find two numbers whose sum is 28 and whose sum of squares is 400.

Answer 1

x+y = 28

x=28_y ..............1st

x²+y² =400 .......2nd

use value of x from ist in equation ....2nd to solve

Answer 2

x +y =28

=>> x= 28_y

x²+y² = 400 ~~~~~~~A

put value of x in equation A and solve