Evaluate
2x\left(x+4\right)
Expand
2x^{2}+8x
Graph
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2\left(x^{2}+4x+4\right)-8
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
2x^{2}+8x+8-8
Use the distributive property to multiply 2 by x^{2}+4x+4.
2x^{2}+8x
Subtract 8 from 8 to get 0.
2\left(x^{2}+4x+4\right)-8
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
2x^{2}+8x+8-8
Use the distributive property to multiply 2 by x^{2}+4x+4.
2x^{2}+8x
Subtract 8 from 8 to get 0.
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