The answer is 10.24695. Which is 10.2 for you!
Answer:

Step-by-step explanation:
Notice from the attached image that -315 degrees is the same as 45 degrees.
Recall as well that the csc function is defined as the reciprocal of the sine function: 
Then, you need to evaluate 
Y= -2x²-3x+2, (form y = ax² +b .x + c
The parabola opens downward & hence it's Vertex is a MAXIMUM.
We know that the axis of symmetry is -b/2a ==>3/(-4) ==>
x= - 3/4 (axis of symmetry. At x=-3/4 , y = 25/8 = 3.125
Hence the axis of symmetry is x= - 3/4 & the vertex is at (-3/4, 25/8)
Answer:
5sqrt3
Step-by-step explanation:
Using the pythagorean theorem, we have a^2+4^2=9^2
a^2 + 16 = 81
a^2 = 75.
a = sqrt75.
75 = 25*3. 25 is a perfect square, so sqrt75 = 5sqrt3