X=72 cause 180-(51+57) so 180-108 and the triangle is acute cause all of the angle measures are below 90 degrees.
So your answer is
x=72
Acute Triangle
Use the chain rule.
Let u = 25sin²(x), such that dy/dx = dy/du · du/dx


The answer to the question is
-8 (3x-4)
Adding a negative is same as subtraction
-5+78-32
73-32
41