How do you solve -6 - x/4 (that's division< = -5

How do i get the answer for 2/3 * 10/3

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.

Simplify the algebraic expression 8y-2(y+4)