System A has ONE real solution
System B has NO real solutions
System C has ONE real solution
It depends if the negative number is bigger than the positive number your answer will be a negative number/answer for example -9 - 4 your answer would be -5 since the negative number is bigger it will be the other way around for a positive number if the positive number is bigger than the negative number your answer will be positive for example 5 - -2 = 3 or positive 3.
If we discuss this as if it is a triangle then the "rise" is the vertical side and the "run" is the adjacent side.
So the ratio of the rise to the run is 8 / 15 which equals
<span>
<span>
<span>
0.5333333333
</span>
</span>
</span>
To find the angle of this roof pitch we look up the arc tangent of
<span>
<span>
<span>
0.5333333333
</span>
</span>
</span>
and we find that is 28.072 Degrees
Trigonometry Calculator:
http://www.1728.org/trigcalc.htm
<span>y=1/3 x - 2
3y = x - 6
x - 3y = 6 ...this is standard form</span>
Use 0 as the y value then solve for x. answer: 3
