Use Pythagorean Theorem which states that in a right triangle:

, where a and b are the legs, and c is the hypotenuse.

Take the square root of both sides to solve for x.

The answer is 26.
<span>f(x) = x</span>² <span>+ 12x + 6 </span>→ y = x² + 12x + 6<span>
Let us convert the standard form into vertex form.
1) Complete the squares. Isolate x</span>² and x terms.
<span>y - 6 = x</span>² + 12x
<span>
2) Create the perfect square trinomial. Whatever number is added on one side must also be added on the other side.
y - 6 + 36 = x</span>² + 12x + 36<span>
y + 30 = (x + 6)</span>²
<span>y = (x + 6)</span>² - 30 ← Vertex form
<span>
To check:
y = (x + 6) (x + 6) - 30
y = x</span>² + 6x + 6x + 36 - 30
<span>y = x</span>² + 12x + 6<span>
The zero that could be added to the given function is 36, -36</span>
The measure of angle 1 and 2 should add up to 180°, because it forms a straight line. The same goes for the sum of angle 3 and 4.
Since we are given the measure of angle 2, we can find the measure of angle 1 by subtracting 143° from 180°.
180°-143° = 37°
We know that the intersecting lines form 2 sets of vertical angles, which are congruent. This means that the angles opposite from each other have the same measure. Therefore, both angle 2 & 4 have a measure of 143°, while angle 1 & 3 have a measure of 37°.
3 (k-12) = k-30
3k - 36 = k - 30
3k - k = -30 + 36
2k = 6
k = 3