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What is 9a - 3 (2a - 4) = 15

What is 9a - 3 (2a - 4) = 15-example-1
User BobBrez
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2 Answers

4 votes
The answer is a=1

Here's the math:

9a-3(2a-4)=15

9a-6a+12=15-------------------------------Distribute the -3 across the parenthesis

3a+12=15-----------------------------------Combine like terms

3a=3----------------------------------------Subtract 12 from both sides

a=1-------------------------------------------Divide 3 from both sides

Hope this helped!! :))
User Tatianna
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5 votes
9a + -3(2a + -4) = 15 Reorder the terms: 9a + -3(-4 + 2a) = 15 9a + (-4 * -3 + 2a * -3) = 15 9a + (12 + -6a) = 15 Reorder the terms: 12 + 9a + -6a = 15 Combine like terms: 9a + -6a = 3a 12 + 3a = 15 Solving 12 + 3a = 15 Solving for variable 'a'. Move all terms containing a to the left, all other terms to the right. Add '-12' to each side of the equation. 12 + -12 + 3a = 15 + -12 Combine like terms: 12 + -12 = 0 0 + 3a = 15 + -12 3a = 15 + -12 Combine like terms: 15 + -12 = 3 3a = 3 Divide each side by '3'. a = 1 Simplifying a = 1
User Roi Divon
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