Answer:
19°
Step-by-step explanation:
I have attached an image showing this elevation.
From the image, let's first find the angle A by using cosine rule.
Thus;
8.1² = 5.5² + 13.1² - 2(5.5 × 13.1)cos A
65.61 = 30.25 + 171.61 - 144.1cos A
144.1cos A = 171.61 + 30.25 - 65.61
144.1cosA = 136.25
cosA = 136.25/144.1
cosA = 0.9455
A = cos^(-1) 0.9455
A = 19°
About $80
5.29*16.3=86.227 which is closest to 80
It would be 8√17 because the seventeens don't change only the one that subtracting 9.
It's suppose to be -18 so I guess no real number....
sin x = cos 54 = sin (90-54) = sin 46
Hence x = 46 deg
Same technique. Sin 21 = cos (5x+9) = sin (90-5x-9)
81-5x = 21
Or 5x = 60
Or x = 12 deg
hope it helps