Solve for y
y=12
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7y=4\times 21
Multiply both sides of the equation by 140, the least common multiple of 20,35.
7y=84
Multiply 4 and 21 to get 84.
y=\frac{84}{7}
Divide both sides by 7.
y=12
Divide 84 by 7 to get 12.
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