Question

Find the value of b: -4b + x = 7 8b + 2x = -9

Answer 1

b = -23/16

Explanation:

The variable x can be eliminated from the system by multiplying the first equation by -2 and adding that to the second equation.

-2(-4b +x) +(8b +2x) = -2(7) +(-9)

16b = -23 . . . . . collect terms

b = -23/16 . . . . divide by the coefficient of b

The value of b is -23/16 = -1 7/16.