[solving equations part 2][section 11]

(1.) 7x - 3x = 8 here is the problem

4x = 8 combine like terms
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4 4 divide each side by 4

x = 2 divide and cancel

result: x = 2

(2.) 15 = 7x - 2x here is the problem

15 = 5x combine like terms
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5 5 divide each side by 5

3 = x divide and cancel

result: x = 3

(3.) 2(x - 5) = 4 here is the problem

2x - 10 = 4 multiply thru parentheses

+10 +10 add 10 to each side
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2x = 14 add
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2 2 divide each side by 2

x = 7 divide and cancel

result: x = 7

(4.) 2x + 3(x + 5) = 0 here is the problem

2x + 3x + 15 = 0 multiply thru parentheses

5x + 15 = 0 combine like terms

-15 -15 subtract 15 from each side
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5x = -15 subtract
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5 5 divide each side by 5

x = -3 divide and cancel

result: x = -3

(5.) -7b + 4(2b - 3) = 16 here is the problem

-7b + 8b - 12 = 16 multiply thru parentheses

b - 12 = 16 combine like terms

+ 12 +12 add 12 to each side
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b = 28 add

result: b = 28

(6.) 2b + 4(b - 6) = 12 here is the problem

2b + 4b - 24 = 12 multiply thru parentheses

6b - 24 = 12 combine like terms

+24 +24 add 24 to each side
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6b = 36 add
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6 6 divide each side by 6

b = 6 divide and cancel

result: b = 6

(7.) x - 4(3 - x) = 0 here is the problem

x - 12 + 4x = 0 multiply thru parentheses

5x - 12 = 0 combine like terms

+ 12 +12 add 12 to each side
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5x = 12 add
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5 5 divide each side by 5

x = 2.4 divide and cancel

result: x = 2.4

(8.) -4(x - 9) + 5 = 1 here is the problem

-4x + 36 + 5 = 1 multiply thru parentheses

-4x + 41 = 1 combine like terms

4x - 41 = -1 multiply thru by -1

+ 41 +41 add 41 to each side
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4x = 40 add
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4 4 divide each side by 4

x = 10 divide and cancel

result: x = 10

(9.) 6 - (m - 4) = 18 here is the problem

6 - m + 4 = 18 multiply thru parentheses

10 - m = 18 combine like terms

-10 + m = -18 multiply thru by -1

+ 10 + 10 add 10 to each side
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m = -8 add

result: m = -8

(10.) -8 - (9 - 4m) = 15 here is the problem

-8 - 9 + 4m = 15 multiply thru parentheses

4m - 17 = 15 combine like terms

+ 17 +17 add 17 to each side
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4m = 32 add
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4 4 divide each side by 4

m = 8 divide and cancel

result: m = 8