Question

-4a/5-9=1
A) =
B) the solution is all real numbers
C) there is no solution

Answer 1

A) a = -12.5

Explanation:

The variable, a, has been multiplied by -4/5 and then -9 added to the product. To solve for a, we undo these operations in reverse order.

To undo addition of -9, we add 9 to both sides of the equation.

-4a/5 = 10

To undo multiplication by -4/5, we multiply the equation by its reciprocal:

(-5/4)(-4a/5) = 10(-5/4)

a = -50/4 = -12.5

The one solution is a=-12.5.