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81y^{2}-16x^{2}
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81y^{2}-16x^{2}
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\left(-4x-\left(-9y\right)\right)\left(4x+9y\right)
To find the opposite of 4x-9y, find the opposite of each term.
\left(-4x+9y\right)\left(4x+9y\right)
The opposite of -9y is 9y.
-16x^{2}-36xy+36yx+81y^{2}
Apply the distributive property by multiplying each term of -4x+9y by each term of 4x+9y.
-16x^{2}+81y^{2}
Combine -36xy and 36yx to get 0.
\left(-4x-\left(-9y\right)\right)\left(4x+9y\right)
To find the opposite of 4x-9y, find the opposite of each term.
\left(-4x+9y\right)\left(4x+9y\right)
The opposite of -9y is 9y.
-16x^{2}-36xy+36yx+81y^{2}
Apply the distributive property by multiplying each term of -4x+9y by each term of 4x+9y.
-16x^{2}+81y^{2}
Combine -36xy and 36yx to get 0.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}