Question

What are these about ? Can anyone explain to me this part? PLEASE :(

Answer 1

It sets a condition: When thex and y units add to 90, tanx= recoprocal of tany

The chart gives the values of trig. function when at certain degrees. When we looks ar tanΘ, we are given the x and y values, becuase tanΘ= y/x

Answer 2

The answer is 45 degrees

The reciprocal of any function is 1 over the function

for example, the reciprocal of
`sin\ x \ \ \ is \ \ \ (1)/(sin \ x)`

So
if x + y = 90

The value of x and y should be the same bcz


`tan \ x = (1)/(tan \ y)` means that the function is reciprocal and the measure of their angles (x and y) have to be the same

45 + 45 = 90

x = 45
y = 45