Here is some thoughts on this:
cos 57 = sin (90-57) = sin 33
so cos 57 . cosec 33 = cos 57 / sin 33 = sin 33 / sin33 = 1
2 cos 60 = 2 * 1/2 = 1
so the last 2 parts work out to 0
now we have to find cos 70 / sin 20
sin 20 = cos 70 so this comes to 1
so finally the answer is 1
A= pi times r*r so if you are using 3.14 as pi the answer is 78.5 because 5x5=25
25x3.14=78.5
Answer:
Step-by-step explanation:
y ≤ 5x - 1
- 5x + y ≤ - 1
5x - y ≥ 1
X = ones, y = fives
x + y = 19....x = 19 - y
x + 5y = 59
19 - y + 5y = 59
19 + 4y = 59
4y = 59 - 19
4y = 40
y = 40/4
y = 10 <=== there are 10 five dollar bills
x + y = 19
x + 10 = 19
x = 19 - 10
x = 9 <=== there are 9 one dollar bills