10
x42,300
-------------
00
000
3,000
20,000
400,000
-------------
423,000
Start with an equation summing all the angles in this triangle:
180 = <M + <N + <P
we are given <M and <N but not <P. But, since MN=NP, the angle <P is the same as the angle <M (isosceles, make a drawing to see). So
180 = 2<M + <N
180 = 2(3x+1) + x-11
180 = 7x - 9
x = 27
<P = 3*27+1 = 82 degrees
The perimeter of the triangle would be B)18. the triangle's sides are equal and you can tell by the single lines on each side symbolizing that all the sides are equal. To find perimeter, you have to add all sides together, and in this case it is 6. When 6 is added three times, it equals 18, which is the answer.
