Evaluate
\left(x-3y\right)\left(x+7y\right)
Expand
x^{2}+4xy-21y^{2}
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x^{2}-3xy+7yx-21y^{2}
Apply the distributive property by multiplying each term of x+7y by each term of x-3y.
x^{2}+4xy-21y^{2}
Combine -3xy and 7yx to get 4xy.
x^{2}-3xy+7yx-21y^{2}
Apply the distributive property by multiplying each term of x+7y by each term of x-3y.
x^{2}+4xy-21y^{2}
Combine -3xy and 7yx to get 4xy.
Examples
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Limits
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