118k views
4 votes
Find the measure of angle N in the triangle . first find the value of y and then plug it in. please show work. help

Find the measure of angle N in the triangle . first find the value of y and then plug-example-1
User Nevyn
by
3.8k points

1 Answer

3 votes

Answer:

Explanation:

By the Isosceles Triangle Theorem, angle O and angle M are congruent because the sides across from each of these angles are congruent. therefore, O = M = 4y - 15. Since, by the Triangle Angle-Sum Theorem all the angles of a triangle have to add up to equal 180 AND angle O and angle M are the same:

7y + 4y - 15 + 4y - 15 = 180 and

15y - 30 = 180 and

15y = 210 so

y = 14. Plug 14 in for y in 7y and get that

∠N = 98°

User John Bernard
by
4.8k points