The equation for 17 + 51 = 68 verify goldbach's conjecture for the number 68

Which best explains why this triangle is or is not a right triangle?

In a column proof the right column states your reasons

Write an equation of the line that passes through the point (2, 3) and is perpendicular to the line x = -1. a) y = 1 b) y = 3 c) y = 0 eliminate d) y = -3