Solve for k
k=9
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3\left(k-9\right)+90=5\times 2k
Multiply both sides of the equation by 15, the least common multiple of 5,3.
3k-27+90=5\times 2k
Use the distributive property to multiply 3 by k-9.
3k+63=5\times 2k
Add -27 and 90 to get 63.
3k+63=10k
Multiply 5 and 2 to get 10.
3k+63-10k=0
Subtract 10k from both sides.
-7k+63=0
Combine 3k and -10k to get -7k.
-7k=-63
Subtract 63 from both sides. Anything subtracted from zero gives its negation.
k=\frac{-63}{-7}
Divide both sides by -7.
k=9
Divide -63 by -7 to get 9.
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