60 degrees
This triangle is a right triangle, which means One angle measure of the triangle is 90 degrees. And the given angle is 40 degrees. The total sum of all the angles in a triangle is 180 degrees.
So if you add 40 + 90 + x = 180
You get 130 + x = 180
If you subtract 180 - 130
You get 60.
If I didn’t explain it good enough, let me know so I can explain it better.
If this helped, pls mark branliest.
