100 points! Giving out points until I run out lolololol

The triangles are similar. what is the value of x? show your work.

List x1, x2, x3, x4 where xi is the midpoint endpoint of the five equal intervals used to estimate the area under the curve of f(x) between x = 0 and x = 10.

What is the factor form of x^2-9x+14