Evaluate
9y^{2}-x^{2}
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9y^{2}-x^{2}
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\left(-x-\left(-3y\right)\right)\left(3y+x\right)
To find the opposite of x-3y, find the opposite of each term.
\left(-x+3y\right)\left(3y+x\right)
The opposite of -3y is 3y.
-3xy-x^{2}+9y^{2}+3yx
Apply the distributive property by multiplying each term of -x+3y by each term of 3y+x.
-x^{2}+9y^{2}
Combine -3xy and 3yx to get 0.
\left(-x-\left(-3y\right)\right)\left(3y+x\right)
To find the opposite of x-3y, find the opposite of each term.
\left(-x+3y\right)\left(3y+x\right)
The opposite of -3y is 3y.
-3xy-x^{2}+9y^{2}+3yx
Apply the distributive property by multiplying each term of -x+3y by each term of 3y+x.
-x^{2}+9y^{2}
Combine -3xy and 3yx to get 0.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
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}