SOLUTION: I am having a problem with the equations can you please help me? ( x - 4 )/2 - 1/5 = (7x + 1)/20 I do not understand what to do in this equation.

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: I am having a problem with the equations can you please help me? ( x - 4 )/2 - 1/5 = (7x + 1)/20 I do not understand what to do in this equation.       Log On


   

Question 110842: I am having a problem with the equations can you please help me?
( x - 4 )/2 - 1/5 = (7x + 1)/20
I do not understand what to do in this equation.
Found 2 solutions by scott8148, ankor@dixie-net.com:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
multiplying by 20 gives 10(x-4)-4=7x+1 ... 10x-44=7x+1

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
( x - 4 )/2 - 1/5 = (7x + 1)/20
:
Assume you mean:
%28%28x-4%29%29%2F2 - 1%2F5 = %28%287x%2B1%29%29%2F20
:
If we multiply the equation by 20 we eliminate the denominators
20*%28%28x-4%29%29%2F2 - 20*1%2F5 = 20*%28%287x%2B1%29%29%2F20
:
Cancel out the denominators, leaving us with:
10(x-4) - 4(1) = 7x + 1
:
10x - 40 - 4 = 7x + 1
:
10x - 7x - 44 = 1; subtracted 7x from both sides
:
3x = 1 + 44; added 44 to both sides
:
3x = 45
:
x = 45/3
:
x = 15
:
:
It's a good idea to check solution by substituting 15 for x in the original equation
%28%28x-4%29%29%2F2 - 1%2F5 = %28%287x%2B1%29%29%2F20
:
%28%2815-4%29%29%2F2 - 1%2F5 = %28%287%2815%29%2B1%29%29%2F20
:
11%2F2 - 1%2F5 = %28%28105%2B1%29%29%2F20
:
11%2F2 - 1%2F5 = 106%2F20
:
Put all the fraction over 20
110%2F20 - 4%2F20 = 106%2F20
:
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