Solve an equation by multiplying by a reciprocal

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Use the substitution method

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Solve an equation by multiplying by a reciprocal

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Solve an equation by multiplying by a reciprocal EXAMPLE 5 Solve an equation by multiplying by a reciprocal x = 4. 2 7 – Solve SOLUTION 7 2 – The coefficient of x is . 7 2 – The reciprocal of . is x = 4 2 7 – Write original equation. ( ) x ) = 2 7 – 4 2 Multiply each side by the 7 – reciprocal, .

Solve an equation by multiplying by a reciprocal EXAMPLE 5 Solve an equation by multiplying by a reciprocal x = –14 Simplify. ANSWER The solution is –14. Check by substituting –14 for x in the original equation. x = 4 2 7 – CHECK Write original equation. (–14) = 4 ? 2 7 – Substitute –14 for x. 4 = 4 Simplify. Solution checks.

GUIDED PRACTICE for Example 5 Solve the equation. Check your Solution. w = 10 5 6 13. ANSWER 12

GUIDED PRACTICE for Example 5 Solve the equation. Check your Solution. p = 14 2 3 14. ANSWER 21

GUIDED PRACTICE for Example 5 Solve the equation. Check your Solution. 15. 9 = –3 4 m ANSWER –12

GUIDED PRACTICE for Example 5 Solve the equation. Check your Solution. 16. –8 = –4 5 v ANSWER 10