Question
Solve the following quadratic equations by factorization:
$25x(x + 1) = -4$
$25x(x + 1) = -4$
✓
Answer
We have been given
$25x(x + 1) = -4$
$25x^2 + 25x + 4 = 0$
$25x^2 + 20x + 5x + 4 = 0$
$5x(5x + 4) + 1(5x + 4) = 0$
$(5x + 1)(5x + 4) = 0$
Therefore,
$5x + 1 = 0$
$5x = -1$
$\text{x}=\frac{-1}{5}$
Or, $5x + 4 = 0$
$5x = -4$
$\text{x}=\frac{-4}{5}$
Hence, $\text{x}=\frac{-1}{5}$ or $\text{x}=\frac{-4}{5}$
$25x(x + 1) = -4$
$25x^2 + 25x + 4 = 0$
$25x^2 + 20x + 5x + 4 = 0$
$5x(5x + 4) + 1(5x + 4) = 0$
$(5x + 1)(5x + 4) = 0$
Therefore,
$5x + 1 = 0$
$5x = -1$
$\text{x}=\frac{-1}{5}$
Or, $5x + 4 = 0$
$5x = -4$
$\text{x}=\frac{-4}{5}$
Hence, $\text{x}=\frac{-1}{5}$ or $\text{x}=\frac{-4}{5}$
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