How do you solve \frac { 1} { 7} y + \frac { 1} { 8} y - \frac { 1} { 56} y = y - \frac { 3} { 8}?

2 Answers
Nov 7, 2016

y = 1/2

Explanation:

Step 1) Put all like terms over a common denominator.
Step 2) Solve for y while keeping the equation balanced.

(8/8)1/7y + (7/7)1/8y - 1/56y = 56/56y - 3/8

8/56y + 7/56y - 1/56y = 56y/56 - 3/8

14/56y = 56/56y - 3/8

14/56y - 14/56y + 3/8 = 56/56y - 3/8 - 14/56y + 3/8

3/8 = 56/56y - 14/56y

3/8 = 42/56y

(56/42)3/8 = (56/42)42/56y

1/2 = y

See calculation below.
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