Question

Solve 7x — 20 =3 (4+x)

Answer 1

To solve this, you need to isolate/get the variable "x" by itself in the equation:

7x - 20 = 3(4 + x)   Distribute/multiply 3 into (4 + x)

7x - 20 = (3)4 + (3)x

7x - 20 = 12 + 3x      Subtract 3x on both sides

7x - 3x - 20 = 12 + 3x - 3x

4x - 20 = 12     Add 20 on both sides

4x - 20 + 20 = 12 + 20

4x = 32    Divide 4 on both sides

$\frac{4x}{4} =\frac{32}{4}$

x = 8

PROOF

7x - 20 = 3(4 + x)       Plug in 8 for x

7(8) - 20 = 3(4 + 8)

56 - 20 =3(12)

36 = 36