Answer:
A. 37.5°
Step-by-step explanation:
∠SPT can be considered an inscribed angle in the circumcircle. In that circle, arc ST would have a measure of 360°/8 = 45°. Angle y° is half that measure, so is 22.5°.
The external angles of a regular octagon are 360°/8 = 45°, so that is the measure of angles UTW and UVW. It is also the amount by which reflex angle TUV exceeds 180°.
The sum of the interior angles of quadrilateral TUVW is ...
45° +225° +45° +3x° = 360°
Then 3x° = 45° and x° = 15°.
Then the sum of interest is ...
x° + y° = 15° + 22.5° = 37.5°
I'll do the first graph.
We can easily find the y intercept by inputting 0 for x.
y = -2(0) + 7
y = 7
The y-intercept is (0, 7)
To find the x intercept, isolate x.
y = -2x + 7
Add 2x to both sides.
2x + y = 7
Subtract y from both sides.
2x = -y + 7
Divide by 2 on both sides.
x = -1/2y + 3.5
Input 0 for y.
x = -1/2(0) + 3.5
x = 3.5
The x intercept is (3.5, 0)
Now try the rest own your own! :)
