Answer:
If P = (x,y) then formulas for each trigonometric functions are:
sin x = y/r
cos x = x/r
tan x = y/x
cot x = x/y
sec x = r/x
cosec x = r/y
where r = √(x²+y²).
First find r:
r = √(13²+84²)=√(169+7056)=√7225=85.
Then just substitute:
sin x = 84/85
cos x = 13/85
tan x = 84/13
cot x = 13/84
sec x = 85/13
cosec x = 85/84
The answer would be a hope it helps
2x^2 - 11 = 87
2x^2 = 87 + 11 = 98
x^2 = 98/2 = 49
x = sqrt (49) = + or - 7
B is the answer because you have to math it