A number is 10 more than another number. Twice the sum of the two numbers is 12. Find the two numbers. (Enter your answers as a comma-separated list.)

Answer 1

We translate this into algebra.

a=b+10

2(a+b)=12

We then substitute the first equation's value for a into the second equation.

2(b+10+b)=12

2(2b+10)=12

4b+20=12

b+5=3

b=-2

Then we substitute this value for b back into the first equation.

a=b+10

a=-2+10

a=8

The two numbers are 8 and -2.