[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