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Solve for x
2(2x-5) + 1 = x - 8 -5x
Please include steps, so maybe I can understand this. Thank You

2007-04-29 03:23:00 · 7 answers · asked by ambi565 2 in Science & Mathematics Mathematics

7 answers

2(2x - 5) + 1 = x - 8 - 5x

2*2x - 2*5 + 1 = x - 5x - 8

4x - 10 + 1= - 4x - 8

4x - 9 = -4x - 8 // + 4x

4x + 4x - 9 = -4x + 4x - 8

8x - 9 = -8 // + 9

8x - 9 + 9 = -8 + 9

8x = 1 // divide by 8

8x/8 = 1/8

x = 1/8

2007-04-29 03:33:28 · answer #1 · answered by Amit Y 5 · 1 0

2(2x-5) + 1 = x - 8 - 5x

All the variable (x ) should be in the left side and all constants in the right side

Let do the multiplication first

2(2x-5) + 1 = x - 8 - 5x
4x - 10 + 1 = x - 8 - 5x
4x - 9 = -8 -4x
Transfer the constant to the right side by adding its inverse to both sides
4x - 9 + 9 = - 8 + 9 - 4x
4x = 1 - 4x
Transfer the variable to the left side by adding its inverse to both sides
4x + 4x = 1 - 4x + 4x
8x = 1
Divide by 8
8x/8 = 1/8
x = 1/8 ===> the answer
To check, substitute the value of x in the original equation

2(2x-5) + 1 = x - 8 - 5x
2( 2(1/8) - 5) + 1 = 1/8 - 8 - 5(1/8)
2( 1/4 - 5) + 1 = 1/8 - 8 - 5/8
1/2 - 10 + 1 = -8 - 1/2
1/2 - 9 = -8 1/2
-8 1/2 = -8 1/2

2007-04-29 03:36:53 · answer #2 · answered by detektibgapo 5 · 0 0

2(2x-5) + 1 = x - 8 -5x
Expand the bracket
4x - 10 + 1 = x - 8 - 5x

combine the numbers and x's

4x - 9 = -4x - 8

at 4x to both sides
8x - 9 = -8
at 9 to both sides
8x = 1
divide by 8
x = 1/8

2007-04-29 03:27:56 · answer #3 · answered by welcome news 6 · 0 0

Using the distributive property of multiplication over addition (or in this case, subtraction, which is merely adding a negative number), 2(2x-5) becomes 4x-10.
So on the left side of your equation, you have 4x-10+1. Add the -10 and +1 and you have -9. So your complete expression there is 4x-9.
+
+
On the right side of your equation, you have x-8-5x. -5x combines with 1x to make -4x. So on the right side of the equation, you have -4x -8.
+
+
Written out, the equation is now: 4x-9=-4x-8.
+
+
Now, solve for x:
Move the -4x across the equals sign and it changes signs to become +4x. You can also look at this as 'adding 4x to both sides of the equation'
Now you have 4x+4x -9=-8.
This is 8x-9=-8 after you add your x's together.
+
+
8x-9=-8
Now move your -9 across the equals sign and it becomes +9 on the other side (also can be seen as adding ( to both sides of the equation).
This gives you 8x=-8+9
Which is 8x=1 (after you have added -8 and +9)
+
+
Your goal has been to isolate the x on one side of the equation.
Now you have 8x=1
Divide 8x by 8. This means you have to divide whatever is on the other side of the equals sign by 8 too.
So 8x/8=1/8
x =1/8
You goal has been to get x by itself with the simple coefficient of 1. After all that, it equals whatever remains on the other side of the equals side, after all you have done.
Answer: x=1/8

2007-04-29 03:48:23 · answer #4 · answered by kathyw 7 · 0 0

2(2x-5) + 1 = x - 8 - 5x
4x - 10 + 1 = -4x - 8
4x - 9 = -4x - 8
8x = 1
x = 1/8

2007-04-29 03:30:54 · answer #5 · answered by Anonymous · 0 0

2(2x - 5) + 1 = x - 8 - 5x

4x - 10 + 1 = - 4x - 8

4x - 9 = - 4x - 8

4x - 9 + 4x = - 4x - 8 + 4x

8x - 9 = - 8

8x - 9 + 9 = - 8 + 9

8x = 1

8x / 8 = 1 / 8

x = 1 / 8

- - - - - - - - -s-

2007-04-29 03:37:56 · answer #6 · answered by SAMUEL D 7 · 0 0

Welcome and Cal Silv have your answer (x = 1/8).

You realize (?) that you can check your answer by plugging it into the left and right side (separately) of your original equation and seeing whether each side simplifies to the same thing.
---------------
LHS for x = 1/8

2(2/8 - 5) + 1 = 4/8 - 10 + 1 = - (8&1/2)

RHS for x = 1/8

1/8 - 8 - 5/8 = - 8 - 4/8 = (same as LHS, above)

So answer valid/checks.

2007-04-29 03:34:53 · answer #7 · answered by answerING 6 · 0 0

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