a. if y = -30 when x = 15, what is the value of x when y = 60?
y =
x=
b. if y = 8 when x = 3, find y when x = 45.
y=
y=
c. find y when x = -6, if y = 15 when x = -5.
y=
y=

a.
y = -30 ... x = 15
y = 60 ... x = ?

-30 * x = 15 * 60
x = - 15 * 60 / 30
x = -30

b.
y = 8 ... x = 3
y = ? ... x = 45

8 * 45 = y * 3
y = 8 * 45 / 3
y = 120

c.
x = -6 ... y = ?
x = -5 ... y = 15

-6 * 15 = -5 * y
y = 6 * 15 / 5
y = 18