Evaluate
\left(a-5b\right)\left(4a-b\right)
Expand
4a^{2}-21ab+5b^{2}
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4a^{2}-20ab-ba+5b^{2}
Apply the distributive property by multiplying each term of 4a-b by each term of a-5b.
4a^{2}-21ab+5b^{2}
Combine -20ab and -ba to get -21ab.
4a^{2}-20ab-ba+5b^{2}
Apply the distributive property by multiplying each term of 4a-b by each term of a-5b.
4a^{2}-21ab+5b^{2}
Combine -20ab and -ba to get -21ab.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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