SOLUTION: How would I solve this Equation the fractions confuse me ? : 1)x/3 - 7/8 = 2/5(x + 15/4)

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Question 135751: How would I solve this Equation the fractions confuse me ? :

1)x/3 - 7/8 = 2/5(x + 15/4)

Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
How would I solve this Equation the fractions confuse me ? :
1)x%2F3+-+7%2F8+=+%282%2F5%29%28x+%2B+15%2F4%29
First lets get rid of the parens:
x%2F3+-+7%2F8=2x%2F5+%2B+3%2F2 (note: %282%2F5%29%2815%2F4%29=%2830%2F20%29=3%2F2)
Now our next drill is to find the smallest number that each denominator (3, 8, 5, 2) will divide equally into (LCM) and then we multiply each term by this number. There's several ways to do this but one approach that I like is to take the largest of the denominators and start multiplying it by (1,2,3----etc) 'till we arrive at a number that all denominators divide equally into. In this case the LCM is 120
120%28x%2F3%29-120%287%2F8%29=120%282x%2F5%29%2B120%283%2F2%29 and this equals:
40x-105=48x%2B180 subtract 48x from and add 105 to both sides
40x-48x-105%2B105=48x-48x%2B180%2B105 collect like terms
-8x=285 divide both sides by -8
x=-35.625
CK
-35.625%2F3-0.875=0.4%28-35.625%2B3.75%29
-11.875-0.875=-12.75
-12.75=-12.75


Hope this helps---ptaylor