the image given is
now in a given isoceles triangle, two sides are equal
from the diagram above, 47 and x are equal
now we have the values of two sides i. e 47, 47 (which is was x). we can use these values to find the value of y
rememeber that sum of angles in a given triangle is equal to 180 degrees
from the calculations above, x = 47, y = 86