Evaluate
21\left(7x+2\right)^{2}
Expand
1029x^{2}+588x+84
Graph
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3\left(49x^{2}+28x+4\right)\times 7
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(7x+2\right)^{2}.
21\left(49x^{2}+28x+4\right)
Multiply 3 and 7 to get 21.
1029x^{2}+588x+84
Use the distributive property to multiply 21 by 49x^{2}+28x+4.
3\left(49x^{2}+28x+4\right)\times 7
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(7x+2\right)^{2}.
21\left(49x^{2}+28x+4\right)
Multiply 3 and 7 to get 21.
1029x^{2}+588x+84
Use the distributive property to multiply 21 by 49x^{2}+28x+4.
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