cos(20) = sin(70)
note how 20+70 = 90
The general rule is that if x+y = 90, then cos(x) = sin(y). The rule works in reverse as well. Another way to phrase the rule is cos(x) = sin(90-x).
So,

Note: if the computer doesn't like the answer of "sin 70" then try "sin(70)" and see how that works out. It's also possible that the teacher wants the single numeric value of "70" in the first box rather than the "sine" part to go along with it. Though that would be strange and incorrect since cos(20) = 70 is a false statement.
He had 32 dollars at the beginning of the day
Answer:
x = 11°
I don't know about the second
it's a correct answer.
Answer:
One of the properties of triangle is the opposite of the largest angle is the longest leg and the smallest angle is opposite the shortest leg.
Given the three sides of the triangle with its corresponding angle, we have:
(2m+3) = m∠X
(m-3) = m∠Y
(m+8) = m∠Z
assign value for m; let m = 6
2(6)+3 = 15 = m∠X
6 - 3 = 3 = m∠Y
6 + 8 = 14 = m∠Z
As the sides correspond to its angle, therefore, the largest angle is m∠X and the smallest is m∠Y
The correct one is m∠Y < m∠Z < m∠X