Okay, so on number one I have no idea. I keep getting 20 because 14 - (-3)2 = 14- (-6) which is really 14 + 6=20.
Number 2 is r+15=61
Number 3 I didn't get any of those answers because you have to solve what is in the parenthesis first so3*5= 15+1=16 then you multiply that by two giving you 16*2=32 and 42-32=10
The formula of the line is
y=mx + b
The likes goes through the point (0,0)
that means that y-int = 0, b=0
y=mx
So we need to find only slope.

Draw a perpendicular segment from point C to the midpoint of AB. Using the trig sine function sin 80 = x/6 which gives 5.91 for the perpendicular segment. Using the formula A=1/2bh, A= 1/2 x5.91x2sqrt 2 A= 8.4
$10 because 2 and 3 add together and subtract 15 equals 10
21= 1,3,7,21
30= 1,2,3,5,6,10,15,30
common factors= 1,3