Since A is on the y-axis, 6 is the y-intercept.
m = Δy ÷ Δx
m = (0 + 6) ÷ (6 + 12)
m = 6 ÷ 18
m =

y =

x + 6
This is very easy!! I have attached a picture I have drawn if you are a visual learner... well, everything else like computations is here.
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This is the PYTHAGOREAN THEOREM!!
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If you don't know, it says that the lengths of the legs squared added together all equal the hypotenuse squared in a right triangle!!
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And if you want to know why the "triangle" has a right angle... well, are towers slanted? I mean, other than the Leaning Tower of Pizza. I mean Pisa.
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So... we plug it in!!
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Formula: a^2 + b^2 = c^2.
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Plug it in: 11^2+ 61^2 = c^2
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c^2 = 3842.
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So now what?
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SQUARE ROOT OF EVERYTHING!!
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c = <span>√3842.
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So? c = approximately 61.984.
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Hope I helped!!</span>
To solve quadratics, the most correct and effective way, in my opinion, is the quadratic formula:

<span><span>
Plugging it in, we get:
</span></span>

So the final answer is:

and