The equation is .

Multiply the two factors.

(Using FOIL method)

Product of two different sings is negative.

Product of two same sings is positive.

Combine like terms using distributive property: ac bc = (a b)c.

Rewrite the equation .

Subtract from each side.

Group terms with common factors.

Factor the G.C.F from each grouping.

Combine like terms using distributive property: .

Apply zero product property: If ab = 0 then a = 0, b = 0.

First .

Apply subtraction property of equality: If a = b then a + b = b + a.

Add 7 to each side.

Apply additive inverse property: .

Divide each side by 2.

Second .

Apply addition property of equality: If a = b then a + b = b + a.

Add 1 to each side.

Apply additive inverse property: .

Divide each side by 2.

Check:

To check the solution substitute in .

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The L.C.D of 2, 1 is 2.

The first solution is true.

To check the solution substitute in .

The L.C.D of 2, 1 is 2.

The second solution is true.

The values of .