Since you know that PQ=RQ, you have an equilateral triangle. This makes things very simple.
Angle R should be the same as angle P.
A triangle is equal to 180 degrees.
Add angles P and R. Subtract 180 from the answer you got. That will give you 2a. a divided by 2 will give you a.
Or, since there are two right triangles, you can add 47 and 90. Subtract 180 from that and you will get a.
Area=pi x radius squared so (3.14)(10)squared = 314
7 is the prime factor of 210
Answer is 7.
55+5X=90
5X=90-55
5X=35
X=35/5
X=7
How many times does 12 go into 60?
5 times.
What is 100/5?
20
So, 20%.
You could also just divide 12/60 then get .2 and then realize that it is the same as .20 and that is the same as 20%.