Question

jill is thinking of two numbers. they have the sum of 27 and a difference of 7. what are the two numbers?

Answer 1

a+b=27
a-b=7
if we sum these
a+b+a-b=27+7=34
2a=34 ⇒ a=34/2 ⇒a=17
b=27-a=27-17 ⇒ b=10

Answer 2

17 and 10/ 17+10=27 17-10=7