We know that
sin²x+cos²x=1
so
clear cos x
cos x=(+/-)√[1-sin²x]
in this problem
<span>Angle 0 is in quadrant 1 -----> cos o and sin o are positive
</span>sin o=2/5
cos x=√[1-(2/5)²]----> cos o=√[1-4/25]----> cos o=√[21/25]---> cos o=√21/5
the answer is
cos o=√21/5
Split it into 7 triangles. Half-base of each is 2 so the distance of center to the midpoint of the base is (Pythagoras) square root of (4.62 - 22) = 4.162 triangle is this times 2, and with 7 triangles multiply also by 7 to get an approximate area of 58 sq in.
Answer:
a map of a rectangular park has a length of 4 inches and a width of 6 inches. It uses a scale of 1 inch for every 30 miles
