Question

Given the equation below what is the value of a+b?
1/2(a+3)-b=-6
3a-2b=-5

Answer 1

15

Explanation:

1. 1/2(a+3)-b=-6 ⇒ a+3-2b= -12 ⇒ a-2b= -15

2. 3a-2b= -5

subtract the equations to eliminate 2b:

• 3a+5= a+15
• 2a= 10
• a= 5

then

• b= 10

then

• a+b= 5+10= 15