Suppose y varies directly with x. If x is - 7 when y is 3, what is x when y is - 5?

If they vary directly, u can make a proportion

-7/3 = x/-5 ... - 7 to 3 = x to - 5

cross multiply

(3) (x) = (-7) (-5)

3x = 35

x = 35/3

x = 11 2/3

check ...

-7/3 = (35/3) / - 5

cross multiply

3 (35/3) = (-5) (-7)

35 = 35 (correct)

so when y = - 5, x = 35/3 or 11 2/3