Answer:
y = 14
Angle O is 41 degrees
Step-by-step explanation:
From the question, since we have an isosceles triangle, then the base angles are equal
This means that the angle at M is (4y-15) too
Mathematically, the sum of the angles in a triangle is 180 degrees
Thus;
7y + 4y-15 + 4y-15 = 180
15y-30 = 180
15y = 180+ 30
15y = 210
y = 210/15
y = 14
Angle O is 4y-15
= 4(14) -15 = 56-15 = 41 degrees