Question

The sum of two numbers is 30 and their difference is 12. Find the two numbers.

Answer 1

let the two numbers are x & y

x+y=30...eq(1) &x-y=12....eq(2)

x=30-y then put in the eq(2)

30-y-y=12

30-2y=12

-2y=12-30

-2y= -18

y=9 then we put this answer in to eq(1)

so,x+y=30

x+9=30

x=30-9

x=21

so, the two numbers are (21,9)