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3x^{2}-5x-21
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3x^{2}-5x-21
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x^{2}-4x+\left(-7+2x\right)\left(3+x\right)
Use the distributive property to multiply x by x-4.
x^{2}-4x-21-7x+6x+2x^{2}
Apply the distributive property by multiplying each term of -7+2x by each term of 3+x.
x^{2}-4x-21-x+2x^{2}
Combine -7x and 6x to get -x.
x^{2}-5x-21+2x^{2}
Combine -4x and -x to get -5x.
3x^{2}-5x-21
Combine x^{2} and 2x^{2} to get 3x^{2}.
x^{2}-4x+\left(-7+2x\right)\left(3+x\right)
Use the distributive property to multiply x by x-4.
x^{2}-4x-21-7x+6x+2x^{2}
Apply the distributive property by multiplying each term of -7+2x by each term of 3+x.
x^{2}-4x-21-x+2x^{2}
Combine -7x and 6x to get -x.
x^{2}-5x-21+2x^{2}
Combine -4x and -x to get -5x.
3x^{2}-5x-21
Combine x^{2} and 2x^{2} to get 3x^{2}.
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Limits
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