Hello!
The area of a triangle is always 180°
And we know that angle "A" is 90°
So we can do 180 - 90 = 90
Which means that.
(2x+14) + (4x-26) = 90
You combine like terms
6x - 12 = 90
add 12 to each side.
6x = 102
divide by 6 on both sides
x = 17
So the answer is 17°
Hope this helps!