If n represent number than write an expression for three times the difference of the number amd six increased by four times the number

Let n be the number. The difference of the number and six is n-6. Then three times the difference of the number and six is 3·(n-6). This number 3·(n-6) increased by four times the number n, then

3·(n-6)=4·n.

Solve it:

3·n-3·6=4n,

3n-4n=18,

-n=18,

n=-18.

n=-18 and expression is 3·(n-6)=4·n.

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