$125.4 is the answer to #1
#2 im not sure how the 10% effects the problem. so i cant help you there
Answer: x=18
im assuming that this is a right angle
so if it is then that means the total of the angle should be 90 degrees. so 2x+3x should be equal to 90. Just combine like terms to get that 5x=90 and then isolate the variable (divide by 5 on both sides) so x ends up equaling 18.
so x=18
Answer:

Step-by-step explanation:

Factoring f(x) would give a factor (x-1-2i), so you can divide f(x) by this, leaving (x-3)(x+4)(x-1+2i), so the other roots are:
x=3
x=-4
x=1-2i