1.
If
y
varies inversely as
x
and
y
= 12 when
x
= 7, find
x
when
y
= 2.
A.
10
B.
5
C.
42
D.
7
Hint
2.
If
y
varies directly as the square root of
x
and
x
= 25 when
y
= -15, find
x
when
y
= -108.
A.
x
= -5
B.
x
= 4500
C.
x
= 6
D.
x
= 1500
Hint
3.
If
y
varies inversely as the cube of
x
and
y
= 8 when
x
= 2, find
x
when
y
= 1.
A.
x
= 8
B.
x
= 2
C.
x
= 4
D.
x
= 1
Hint
4.
If
y
varies jointly as
x
and the cube root of
z
,
and
y
= 30 when
x
= -5
and
z
= 27, find y when
z
= -8 and
x
= 0.5.
A.
y
= 4
B.
y
= 2
C.
y
= 20
D.
y
= -2
Hint
5.
Which best describes this graph?
A.
none of these
B.
joint variation
C.
direct variation
D.
inverse variation
Hint