What is the value of a? Enter your answer in the box.

a =

A right triangle with base labeled as 20. The hypotenuse is labeled as 25. The perpendicular is labeled as a. The angle made between the base and the perpendicular is marked as a right angle.

a = 15

Step-by-step explanation:

25^2 = 20^2 + a^2

25^2 - 20^2 = a^2

225 = a ^2

a = 15

$6.42

step-by-step explanation:

the arc length is found by finding the circumference of the full circle (2xpixradius) and then dividing by 4 to find just one quarter of the circle (90 degrees).