Evaluate 8a+12-2ba=-2b=4

Answer 1

8a + 12 - 2ba = -2b = 4 is two equations

(1) -2b = 4

(2) 8a + 12 - 2ba = 4

from (1) we know b = -2 which we can substitue in (2) to get

8a + 12 - 2(-2)a = 4

=> 8a + 4a = 4 - 12 => 12a = -8 => a = -²/₃

Double check with original expression so 8(-²/₃) + 12 - 2(-2)(-²/₃) = -2(-2) = 4

which gives -16/3 + 12 - 8/3 = 4 = 4 and -24/3 + 12 = 4