Solve for x
x = \frac{49}{12} = 4\frac{1}{12} \approx 4.083333333
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42x-28=6\times 5x+21
Multiply both sides of the equation by 42, the least common multiple of 3,7,2.
42x-28=30x+21
Multiply 6 and 5 to get 30.
42x-28-30x=21
Subtract 30x from both sides.
12x-28=21
Combine 42x and -30x to get 12x.
12x=21+28
Add 28 to both sides.
12x=49
Add 21 and 28 to get 49.
x=\frac{49}{12}
Divide both sides by 12.
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