ElectricPavlov

Tan =  -4/3

Arctan(-4/3) = -53.130102354156+180 = 126.869897645844

-53 is the reference angle between  - pi/2   and + pi/2   so....

Think about the coordinate plane   the point    -3 , 4  is in Quadrant 2   and the answer is   126.87 degrees

Auugh....   do you see where you got off-course!   Your boat is now stuck on the reef doing tremendous damage !  

it is    3  *  x    -6            not          3 + x   -6

Not sure where you went off-course....add them all together and equate to 360:

(3x-6)  +  2x   + 108  + 88 = 360     gather 'like terms'

3x + 2x  + (108+88-6) = 360          simplify

5 x + 190 = 360                             subtract 190 from each side of the equation

5x = 170

x = 34

Angle A is  shown as    3 x - 6       3 (34) - 6 = 96 degrees

Add them all together and equate to 360   (as stated in the Question)....then solve for x   and calculate A....

    try to do this yourself,   post here if you need more help!  

Angle 6   and angle 2 are equal.

Using factoring

h = -8t^2 + 40 t

   h =-8t (t-5)      t = 0   and  5        Max is at   (5-0)/2 = 2.5 sec    (midway between the zeroes)

 at 2.5 sec

h = -8(2.5)^2 + 40 (2.5)

      -50 +100= 50 ft                         orderd pair is  (2.5 sec , 50 ft)  

When h = 0   the ball is on the ground.....solve for h=0

0 = -16T^2 + 64T

0=    t(-16 t + 64)            so t = 0 is one choice,,,,this would be before the ball is hit.

0 = -16t+64

16t = 64

t = 4   sec      when the ball lands 

Yeppers !      Sorry , the rest of my answer got   truncated somehow before I posted....

I think the computer needs the smallest number first to recognize your answer as correct or incorrect...... weak programming I think.

Complementary angles   add   to 90 degrees