Okay. For these types of problems, you must do order of operations (PEMDAS). Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction. Mind you that you do these steps from left to right, and multiplication and division is done from left to right. Same thing with addition and subtraction. With that being said, here are your answers if you do the expressions correctly.
1. 12
2. 106
3. 42
We can find the value of x through a proportion. Since these two triangles are similar, their sides are in proportion.
4 is to 12 as 5 is to x
Remember to say 12, not 8! 8 is only part of the whole side. We can also simplify 4 is to 12 to 1 is to 3.
1/3 = 5/x
Cross multiply
x = 15
Hope this helps!
The answer is 98 degrees relative to the axis(probably u or v axis ) due to the fact that complementary angles are 90 degrees or it could be 8 degrees if you take the u or v axis as a constraint axis
