Maths-
SAT
Easy
Question
7a + 3b = 34
9a + 9b = 18
The solution to the given system of equations is (a, b). What is the value of a+ 3b?
- 120
- 4
- -8
- -16
The correct answer is: -8
Subtract the 1st equation from the 2nd to get 2a + 3b = - 1b
Then divide LHS & RHS to get at 3b = - 8
So, Option C.
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