Answer:
A
Step-by-step explanation:
The total class is 10
the number of girls is 7
ratio of girls to total students - 7:10
Answer:
x=2
y=3
Step-by-step explanation:
Answer:
Step-by-step explanation:
Rewrite
100
x
2
100
x
2
as
(
10
x
)
2
(
10
x
)
2
.
(
10
x
)
2
+
60
x
+
9
(
10
x
)
2
+
60
x
+
9
Rewrite
9
9
as
3
2
3
2
.
(
10
x
)
2
+
60
x
+
3
2
(
10
x
)
2
+
60
x
+
3
2
Check the middle term by multiplying
2
a
b
2
a
b
and compare this result with the middle term in the original expression.
2
a
b
=
2
⋅
(
10
x
)
⋅
3
2
a
b
=
2
⋅
(
10
x
)
⋅
3
Simplify.
2
a
b
=
60
x
2
a
b
=
60
x
Factor using the perfect square trinomial rule
a
2
+
2
a
b
+
b
2
=
(
a
+
b
)
2
a
2
+
2
a
b
+
b
2
=
(
a
+
b
)
2
, where
a
=
10
x
a
=
10
x
and
b
=
3
b
=
3
.
(
10
x
+
3
)
2
