Help me, not sure how to solve this, my teacher didn't teach us yet, and I want a solid understanding of it, so the answer will be great! Also will give the most brainliest!

Step-by-step explanation:

10 + 5x = 10 + 5(15)

= 10 + 75

= 85°

4x - 10 = 4(15) - 10

= 60 - 10

= 50°

6x - 5 = 6(15) - 5

= 90 - 5

= 85°

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option