How do you write an expression that represents all quadrantal angles?

The expression that represents all quadrantal angkes is where is an integer.

Step-by-step explanation:

Recall that the quadrantal angles are those coterminal with , , and . Now, notice that all of them can be written as integer multiples of :

Then, if we add to each one of the listed above angles an integer multiple of we get

But the numbers of the form , , and where is an integer, encompass all integers. Thus, all quadrantal angles can be written as

where is an integer.

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6