Vertical angles<span> are the angles opposite each other when two lines cross, so
</span>∠AOB and ∠DOC are vertical.
divide the two:
52.50 / 7 = 7.50 per hour
180-132+x-6x+12=0
48+x-6x+12=0
48-5x+12=0
60-5x=0
-5x=-60
x=12
Answers:
A ' = (-2, -3)
B ' = (0, -3)
C ' = (-1, 1)
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Explanation:
To apply an x axis reflection, we simply change the sign of the y coordinate from positive to negative, or vice versa. The x coordinate stays as is.
Algebraically, the reflection rule used can be written as 
Applying this rule to the three given points will mean....
- Point A = (-2, 3) becomes A ' = (-2, -3)
- Point B = (0, 3) becomes B ' = (0, -3)
- Point C = (-1, -1) becomes C ' = (-1, 1)
The diagram is provided below.
Side note: Any points on the x axis will stay where they are. That isn't the case here, but its for any future problem where it may come up. This only applies to x axis reflections.