Answer:
y = 7
Explanation:
Since all of the sides are of equal length, it is an equilateral triangle and so all of the angles are 60 degrees. That means 3x - 3 and 8y - 4 are each equal to 60 degrees. Since we are only solving for y, we have the equation...
8y - 4 = 60
8y = 60 - 4
8y = 56
y = 56/8
y = 7
So y = 7.