Can someone explain this

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Explanation:

Let x be the unknown angle we want to find. This angle is in degrees.

The diagram shows 19 is the opposite of this angle, and the side 35 is adjacent to the angle.

We use the tangent ratio to tie the two sides together

Note: The notation refers to the inverse tangent, or arctangent.

351°f

step-by-step explanation:

x is the total time in minutes for the free response

you are given number of questions as 15 - m and time per item as 8 minutes

to find x multiply the two givens together:

x = 8 * (15-m) = 8(15-m)