How do you answer these?(4x-2/5)=10, (-x/3)-5=2x, -6x+3-2x=3-8x?

Question

i need help step by step as to how i would find each answer.

Thank You so much.

AND they are obviously written in parenthesis/fraction form but are mean to look as so:

http://i36.tinypic.com/2pqkwmb.jpg

Answer 1

(4x - 2)/5 = 10 (multiply both sides by 5)

4x - 2 = 50 (add 2 to both sides)

4x = 52 (divide both sides by 4)

x = 13 <===ANSWER

-x/3 - 5 = 2x (multiply both sides by -3)

x + 15 = -6x (subtract x from both sides)

15 = -7x (divide both sides by -7)

-15/7 = x <===ANSWER

-6x + 3 - 2x = 3 - 8x (combine like terms)

-8x + 3 = 3 - 8x (add 8x to both sides and subtract 3 from both sides)

0 = 0 (the variables were canceled out and the resulting equation is true, so this equation has infinitely many solutions)

Infinitely many solutions (x = all real numbers) <===ANSWER

Answer 2

1st equation:

4x - 2/5 = 10

4x = 50/5 + 2/5

4x = 52/5

x = 1/4(52/5)

x = 13/5 or 2 3/5

Answer: x = 13/5 or 2 3/5

Proof:

4(13/5) - 2/5 = 10

52/5 - 2/5 = 10

50/5 = 10

10 = 10

2nd equation:

(- x/3) - 5 = 2x

- x/3 = 2x + 5

- x = 6x + 15

7x = - 15

x = - 15/7 or - 2 1/7

Answer: x = - 15/7 or - 2 1/7

Proof:

(- [- 15/7]/3) - 5 = 2(- 15/7)

15/21 - 105/21 = - 30/7

- 90/21 = - 30/7

- 30/7 = - 30/7

3rd equation:

- 6x + 3 - 2x = 3 - 8x

- 8x + 8x = 3 - 3

0 = 0

Answer: this equation has infinite number of solutions.

Answer 3

(4x-2/5) = 10 Multiple both sides by 5, it gets rid of the fraction.

5(4x-2/5) = 10 x 5

20x - 2 = 50

20x = 52

x = 2.6

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Check the work by substituting 2.6 for X:

4(2.6)-2/5 = 10

10.4 - 2/5 = 10  (It helps if you see that .4 is the same as 2/5)

10 = 10

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-x/3-5=2x  This is a very similar problem. First multiply both sides by 3

3(-x/3-5)=3(2x)

-x - 15 = 6x   Add x to both sides to get:

-15 = 7x  Now divide both sides by 7:

-15/7 = x  

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-6x+3-2x=3-8x

This one is easy:

Subtract 3 to both sides and then add 8x to both sides to get:

-6x+3-2x-3+8x=0  -6x and -2x and 8x combine to make 0. So do +3 and -3, so:

0 = 0