Evaluate
\left(4k-1\right)\left(4k+7\right)
Expand
16k^{2}+24k-7
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16k^{2}+24k+9-16
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(4k+3\right)^{2}.
16k^{2}+24k-7
Subtract 16 from 9 to get -7.
16k^{2}+24k+9-16
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(4k+3\right)^{2}.
16k^{2}+24k-7
Subtract 16 from 9 to get -7.
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