1) the area a of a circle with radius is given by the formula a = ir. it
the radius of a circle is 3 centimeters, what is the area of the circle.
(use r = 3.14)

Given two angles of a triangle, we can find the third one by subtracting what we have from 180:
180-63.2-75.9=40.9°.  This means C is correct.
This also means that B is correct; if a triangle is equilateral, all angles must be congruent as well, which these are not.

Cross multiplying the proportion we have:
x*1 = 3(y-3)
1x = 3y - 9
Solving for y, we first cancel the 9 by adding:
1x+9 = 3y
Now we cancel the 3 by dividing:
1x/3 + 9/3 = 3y/3
1/3x + 3 = y
In this format, we can see that the slope (m) is 1/3 and the y-intercept (b) is 3.

Going by the directions for the points P, Q, R, and S, PQ would be parallel to SR and PS would be parallel to QR.  These sides are not parallel to any other sides of this figure.

For the last problem, the vertices given do not form a parallelogram.  There is only 1 pair of parallel sides using these points.