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x^{2}-9y^{2}
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x^{2}-9y^{2}
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\left(5x-15y\right)\left(\frac{1}{5}x+\frac{3}{5}y\right)
Use the distributive property to multiply 5 by x-3y.
5x\times \frac{1}{5}x+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y\times \frac{3}{5}y
Apply the distributive property by multiplying each term of 5x-15y by each term of \frac{1}{5}x+\frac{3}{5}y.
5x^{2}\times \frac{1}{5}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y\times \frac{3}{5}y
Multiply x and x to get x^{2}.
5x^{2}\times \frac{1}{5}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Multiply y and y to get y^{2}.
x^{2}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Cancel out 5 and 5.
x^{2}+3xy-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Cancel out 5 and 5.
x^{2}+3xy+\frac{-15}{5}yx-15y^{2}\times \frac{3}{5}
Multiply -15 and \frac{1}{5} to get \frac{-15}{5}.
x^{2}+3xy-3yx-15y^{2}\times \frac{3}{5}
Divide -15 by 5 to get -3.
x^{2}-15y^{2}\times \frac{3}{5}
Combine 3xy and -3yx to get 0.
x^{2}+\frac{-15\times 3}{5}y^{2}
Express -15\times \frac{3}{5} as a single fraction.
x^{2}+\frac{-45}{5}y^{2}
Multiply -15 and 3 to get -45.
x^{2}-9y^{2}
Divide -45 by 5 to get -9.
\left(5x-15y\right)\left(\frac{1}{5}x+\frac{3}{5}y\right)
Use the distributive property to multiply 5 by x-3y.
5x\times \frac{1}{5}x+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y\times \frac{3}{5}y
Apply the distributive property by multiplying each term of 5x-15y by each term of \frac{1}{5}x+\frac{3}{5}y.
5x^{2}\times \frac{1}{5}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y\times \frac{3}{5}y
Multiply x and x to get x^{2}.
5x^{2}\times \frac{1}{5}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Multiply y and y to get y^{2}.
x^{2}+5x\times \frac{3}{5}y-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Cancel out 5 and 5.
x^{2}+3xy-15y\times \frac{1}{5}x-15y^{2}\times \frac{3}{5}
Cancel out 5 and 5.
x^{2}+3xy+\frac{-15}{5}yx-15y^{2}\times \frac{3}{5}
Multiply -15 and \frac{1}{5} to get \frac{-15}{5}.
x^{2}+3xy-3yx-15y^{2}\times \frac{3}{5}
Divide -15 by 5 to get -3.
x^{2}-15y^{2}\times \frac{3}{5}
Combine 3xy and -3yx to get 0.
x^{2}+\frac{-15\times 3}{5}y^{2}
Express -15\times \frac{3}{5} as a single fraction.
x^{2}+\frac{-45}{5}y^{2}
Multiply -15 and 3 to get -45.
x^{2}-9y^{2}
Divide -45 by 5 to get -9.
Examples
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{ 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}