system of equations

Question

two times a number added to another number is 25. 3 times the first number minus the other number is 20 what're the 2 numbers

Answer 1

2a + b = 25

3a - b = 20

We can add the two equations.

5a = 45

a = 9

2(9) + b = 25

18 + b = 25

b = 7