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How do I solve (a+b)(3a-b)(2a+7b)
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User Mike Spross
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1 Answer

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27 votes

Answer:

Simplifying

-5 + -1(3a + b) + (2a + -7b) = 0

-5 + (3a * -1 + b * -1) + (2a + -7b) = 0

-5 + (-3a + -1b) + (2a + -7b) = 0

Remove parenthesis around (2a + -7b)

-5 + -3a + -1b + 2a + -7b = 0

Reorder the terms:

-5 + -3a + 2a + -1b + -7b = 0

Combine like terms: -3a + 2a = -1a

-5 + -1a + -1b + -7b = 0

Combine like terms: -1b + -7b = -8b

-5 + -1a + -8b = 0

Solving

-5 + -1a + -8b = 0

Solving for variable 'a'.

Move all terms containing a to the left, all other terms to the right.

Add '5' to each side of the equation.

-5 + -1a + 5 + -8b = 0 + 5

Reorder the terms:

-5 + 5 + -1a + -8b = 0 + 5

Combine like terms: -5 + 5 = 0

0 + -1a + -8b = 0 + 5

-1a + -8b = 0 + 5

Combine like terms: 0 + 5 = 5

-1a + -8b = 5

Add '8b' to each side of the equation.

-1a + -8b + 8b = 5 + 8b

Combine like terms: -8b + 8b = 0

-1a + 0 = 5 + 8b

-1a = 5 + 8b

Divide each side by '-1'.

a = -5 + -8b

Simplifying

a = -5 + -8b

Explanation:

User TylersDisplayName
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