9514 1404 393
Answer:
3
Step-by-step explanation:
Vertical angles share a vertex point, and have opposite rays for sides. In short, they are across the point of intersection from each other. Vertical angles do not have a common side (they are <em>not</em> adjacent).
The first part of the problem is to identify angle NCA. That is shown in red in the attachment. The vertical angle is across the point of intersection. It is angle 3.
<span>1/2x+3y/4=5 => (1/2)x + (3/4)y = 5
1/5x+3y/2=2 => (1/5)x + (3/2)y = 2
Eliminate the fractional coefficients: Mult. the first equation by 4 and mult. the second equation by 10:
2x + 15y = 20
</span><span>Multiply the 1st equation by -1:
-</span>2x - 3y = -20
2x + 15y = 20
-------------------
12y = 0, so y = 0. Then the first equation becomes 2x + 3(0) = 20, or
x=10.
Solution is (10,0).