Greetings!
Answer:
x = 8°
Explanation:
Because this triangle is an equilateral triangle, as indicated by the lines which say all lines are congruent, it means every angle, R S and T, are exactly the same amount. 60°
This means that angle S = 60 so:
7x +4 = 60
Simply move the 4 over to the other side, making it a negative:
7x = 60 - 4
7x = 56
So now simply divide both sides by 7:
x = 8
So the value of x is 8°!
Hope this helps!