$$ \begin{aligned} (2x+3)^2-4(x-1)^2 &= 0&& \text{simplify left side} \\[1 em]4x^2+12x+9-4(x^2-2x+1) &= 0&& \\[1 em]4x^2+12x+9-(4x^2-8x+4) &= 0&& \\[1 em]4x^2+12x+9-4x^2+8x-4 &= 0&& \\[1 em]4x^2+12x+9-4x^2+8x-4 &= 0&& \\[1 em]20x+5 &= 0&& \text{ move the constants to the right } \\[1 em]20x &= -5&& \text{ divide both sides by $ 20 $ } \\[1 em]x &= -\frac{5}{20}&& \\[1 em]x &= -\frac{1}{4}&& \\[1 em] \end{aligned} $$

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