17^4dived(17^6)(17^-3)/17^-2

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1

Asap will give brainiest to first person to answer what is the measure of angle b in the triangle? enter your answer in the box.m∠b=