Method: Angles in a triangle add up to 180 The triangle is isosceles so the two interior angles at the bottom will be the same 180-36=144 Because you have two angles at the bottom you need to divide by two so 144/2=72 - that is the interior angle To find y, all you need to do now is 360-72 = 288 (because angles round a point add up to 360) And you have your answer Hope this helps!
The angles in a isosceles triangle add up to 180 degrees. so 180 degrees take away 36 degrees = 144 degrees. base angles in a isoceles triangle are equal so 144 divided by 2 = 72 degrees. so to find out y you do 360 - 72 = 288 degrees therefore y = 288degrees
