Question

question
solve the following quadratic equation for all values of x in simplest form.
4(x - 9)^2 - 20 = -4
answer attempt 1 out of 2
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Explanation:

Step1: Isolate the squared term

Add 20 to both sides.
$$4(x-9)^2 - 20 + 20 = -4 + 20$$
$$4(x-9)^2 = 16$$

Step2: Simplify the equation

Divide both sides by 4.
$$\frac{4(x-9)^2}{4} = \frac{16}{4}$$
$$(x-9)^2 = 4$$

Step3: Take square root of both sides

Apply square root to isolate $x-9$.
$$x-9 = \pm\sqrt{4}$$
$$x-9 = \pm2$$

Step4: Solve for x

Add 9 to both sides.
$$x = 9 \pm 2$$

Answer:

$x = 11$ and $x = 7$