\(=4\left(4x^2+20x+25\right)-2\left(1-9x^2\right)=16x^2+80x+100-2+18x^2=34x^2+80x+98\)
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\(4.\left(2x+5\right)^2-2.\left(3x+1\right).\left(1-3x\right)\)
\(\Leftrightarrow4.\left(4x^2+20x+25\right)-2.\left(1-9x^2\right)\)
\(\Leftrightarrow16x^2+80x+100-2+18x^2\)
\(\Leftrightarrow34x^2+80x+98\)
\(\Leftrightarrow2.\left(17x^2+40x+49\right)\)
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