F(x)=20x when x is 0.25

Write an equation for the function that includes the points (1,4/5) and (2,2/3)

X+ y = 5 ; x - y =3 solve using linear combination

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.