Answer:
x = 8
y = 6
Explanation:
First and foremost, it's an equilateral triangle, therefore all sides and angles are equal.
Knowing that the sum of angle in a triangle is 180°, therefore each angle is 60°.
Then equating (7x+4)° to 60, we have that,
7x+4=60
7x=60-4
7x=56
x=56÷7
x=8.