Solve an equation using subtraction

EXAMPLE 1

Solve x + 7 = 4.

x + 7 = 4 Write original equation.

x + 7 – 7 = 4 – 7 Use subtraction property of equality: Subtract 7 from each side.

x = – 3 Simplify.

ANSWERThe solution is – 3.

Solve an equation using subtraction

EXAMPLE 1

CHECK Substitute – 3 for x in the original equation.

x + 7 = 4 Write original equation.

–3 + 7 = 4? Substitute –3 for x.

4 = 4 Simplify. Solution checks.