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-7b - 4(b + 7) = -3b - 4(b-2)

User Kuzeko
by
3.1k points

2 Answers

3 votes

Answer:

-9 is the required answer of b

Explanation:

-7b - 4(b + 7) = -3b - 4(b-2)

open bracket

-7b-4b-28=-3b-4b+8

-11b-28=-7b+8

-11b+7b=28+8

-4b=36

b=36/-4=-9

User Zach Sugano
by
3.5k points
1 vote

Answer:

b = -9

Explanation:

-7b - 4(b + 7) = -3b - 4(b -2)

First we want to distribute the coefficients across the parentheses. To do so, we multiply the coefficient by every term within the parentheses.

-7b - 4(b + 7) = -3b - 4(b - 2)

-4 • b = -4b

-4 • 7 = -28

-4 • b = -4b

-4 • -2 = 8

Simplify the expression with these new values.

-7b - 4b - 28 = -3b - 4b + 8

Now we want to combine the like terms. First combine the variables.

-7b - 4b - 28 = -3b - 4b + 8

-11b - 28 = -7b + 8

Combine further by adding 7b to both sides.

-4b - 28 = 8

Combine the constants by adding 28 to both sides.

-4b = 36

Isolate b by dividing both sides by -4.

b = -9

This is your answer.

Check your answer by plugging b = -9 back into the original equation.

-7b - 4(b + 7) = -3b - 4(b - 2)

-7(-9) - 4(-9 + 7) = -3(-9) - 4((-9) - 2)

63 - 4(-2) = 27 - 4(-11)

63 + 8 = 27 + 44

71 = 71

Your answer is correct.

Hope this helps!

User Joshua Foxworth
by
3.6k points