Respuesta :

Answer:

16.5

Step-by-step explanation:

Just put in the values of C and y first into the expression.

C = 4x + 5y

Put in values.

51 = 4x + 5(-3)

Evaluate.

51 = 4x + (-15)

Swap positions.

4x + (-15) = 51

Shift (-15) to the other side and change to (+15).

4x = 51 + 15

    = 66

Find x.

x = 66 ÷ 4

x = 16.5