Question
Solve the following quadratic equations by factorization:
$2x^2 + ax - a^2 = 0$
$2x^2 + ax - a^2 = 0$
✓
Answer
$2x^2 + ax - a^2 = 02x^2 + 2ax - ax - a^2 = 0$
$2x(x + a) - a(x + a) = 0$
$(x + a)(2x - a) = 0$
$x + a = 0$ or $2x - a = 0$
$x = -a$ or $\text{x}=\frac{\text{a}}{2}$
Alternate Answer
First calculate $D = b^2 - 4ac$
Then apply $\text{x} = {-\text{b} \pm \sqrt{\text{D}} \over 2\text{a}}$
We get $x = -a$, $\text{x}=\frac{\text{a}}{2}$
$2x(x + a) - a(x + a) = 0$
$(x + a)(2x - a) = 0$
$x + a = 0$ or $2x - a = 0$
$x = -a$ or $\text{x}=\frac{\text{a}}{2}$
Alternate Answer
First calculate $D = b^2 - 4ac$
Then apply $\text{x} = {-\text{b} \pm \sqrt{\text{D}} \over 2\text{a}}$
We get $x = -a$, $\text{x}=\frac{\text{a}}{2}$
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