ummm i need math help it is pre-algebra...?

Question

9. 7(x-13)=56
10. 5x-3099=4027
13. 4(x+19)=212
14. 2x-8=3x-467
5. 212-3x=53
7. x/4+135=342
8. 1506-2x=3x+646-x
11. 8x-153-3x=237+3x
12. x/7+13=62

i dont get how to do them and i dont understand it unless it is step by step....please help and make the steps shorts please.....thank you

Answer 1

For some of your questions, you need to distribute first before you do anything else
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9. 7(x-13) = 56
7x-91 = 56 <<< Distribute
7x = 147 <<< Add 91 to both sides
x = 21 <<< Divide 7 to both sides
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10. 5x-3099 = 4027
5x = 4027+3099 <<< Add 3099 to both sides
5x = 7126 <<< Add 4027 to 3099
x = 1425.2 <<< Divide 5 to both sides
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13. 4(x+19) = 212
4x+23 = 212 <<< Distribute
4x = 189 <<< Subtract 23 to both sides
x = 47.25 <<< Divde 4 to both sides
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14. 2x-8 = 3x-467
2x-3x = -467+8 <<< Put variables on one side and #s on the other (remeber when you go over the equal sign the sign changes, so if its positive, then it'll be negative when you go over and vise versa)
-x = -467+8 <<< Subtract the x's together
-x = -459 <<< Subtract the #s together
x = 459 <<< Divide -1 to both sides (remember, -x is same thing as -(1)x )
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5. 212-3x = 53
212-53 = 3x <<< Put the #s on one side and variables on the other (remeber when you go over the equal sign the sign changes, so if its positive, then it'll be negative when you go over and vise versa)
159 = 3x <<< Subtract 212 to 53
x = 53 <<< Divide 3 to both sides
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7. x/4+135 = 342
x/4 = 206 <<< Subtract 135 to both sides
4(x/4) = (206)4 <<< Multiply 4 to both sides to get rid of the denominator
x = 824 <<< Multiply 4 to 206
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8. 1506-2x = 3x+646-x
-3x+x-2x = 646-1506 <<< Put variables on one side and #s on the other (remeber when you go over the equal sign the sign changes, so if its positive, then it'll be negative when you go over and vise versa)
-4x = 646-1506 <<< Subtract -3x to x, which equals to -2x, then add -2x to -2x, which equals to -4x
-4x = -860 <<< Subtract 646 to 1506
x = 215 <<< Divide -4 to both sides
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11. 8x-153-3x = 237+3x
8x-3x-3x = 237+153 <<< Put variables on one side and #s on the other (remeber when you go over the equal sign the sign changes, so if its positive, then it'll be negative when you go over and vise versa)
2x = 237+153 <<< Subtract 8x to 3x, which equals to 5x, then subtract again 5x to 3x, which equals to 2x
2x = 390 <<< Add 237 to 153
x = 195 <<< Divide 2 to both sides
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12. x/7+13 = 62
x/7 = 62-13 <<< Subtract 13 to both sides
7(x/7) = (49)7 <<< Multiply 7 to both sides to get rid of the denominator
x = 343 <<< Multiply 49 to 7

Answer 2

for number one, you have to didtribute the the seven to the numbers in parenthesis. so in will be 7x-91=56 then you add 91 on both sides to make the left side 7x-0. so it's 7x=147. You then have to divide each side by 7 to get the x by itself so x=21.

for number two you would add 3099 to both side to make it 5x=7126. then divide each side by 5 to get x by itself. so x=1425.2

You would basically have to follow the same steps for each of the problems that comes after that. Need an extra help, just email me...I am glad to assist you.

Answer 3

9... because they are all really the same... You need to have your X on one side of the equation, so first get it out of the parenthesis

you are multipying by 7... so, to get that 7 to the other side of the equation you must divide. Divide BOTH sides of the equation by seven

7(x-13)=56/7
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7

that is x-13=8

then you get rid of the 13. You are subtracting so you must do the opposite on each side (add 13)

x-13+13=8+13

then you can simplify... x=21

Answer 4

you're finding "x" right? it's quite simple. use the distribution property, then use the equality properties. You're basically trying to put "x" on one side and the other numbers on the other side.

i'll use #9 as an example.

7(x-13)=56 <--Given
7x-91=56 <--Distribution Property
7x=147 <-- Addition Property of Equality
x=21 <-- Division Property of Equality

Answer 5

9. 7(x-13) + 56
7x-91=56
7x-91+91=56+91
7x = 147
x=21 (divide both sides by 7)

Whatever you do to one side do to the other

Answer 6

that's really easy. on 9, just multiply and add, on 10 just add and divide by 5, on 13 just multiply and subtract, on 14 get the variable on one side, and the numbers on the other, then add and/or subtract, on 5subtract on 7 add then multiply by 4, on 8 get variables on one side, numbers on the other, then add, on 11 do the same thing, and on 12 subtract and then multiply by 7. not too hard huh?

Answer 7

a million. so its a damaging 25 and upload yet another damaging 25 that could desire to be -50 2.32 subtract a damaging 17, so 32 minus(damaging 17) minus 32 32's pass out and you get -(-17) the different of a damaging is a favorable so its 17

Answer 8

7(x-13)=56
7x-91=56
7x-91+91=56+91
7x=147
147/7=
x=21

5x-3099=4027
5x-3099+3099=4027+3099
5x=7126
x=1425.2

4(x+19)=212
4x+76=212
4x+76-76=212-76


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