X^2-1/4y^2, if x=9, and y=2

4
=
2
9
⋅
(
4
y
−
2
)
4
=
2
9
⋅
(
4
y
-
2
)
Rewrite the equation as
2
9
⋅
(
4
y
−
2
)
=
4
2
9
⋅
(
4
y
-
2
)
=
4
.
2
9
⋅
(
4
y
−
2
)
=
4
2
9
⋅
(
4
y
-
2
)
=
4
Multiply both sides of the equation by
9
2
9
2
.
9
2
⋅
2
9
⋅
(
4
y
−
2
)
=
9
2
⋅
4
9
2
⋅
2
9
⋅
(
4
y
-
2
)
=
9
2
⋅
4
Simplify both sides of the equation.
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4
y
−
2
=
18
4
y
-
2
=
18
Move all terms not containing
y
y
to the right side of the equation.
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4
y
=
20
4
y
=
20
Divide each term by
4
4
and simplify.
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y
=
5

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