What does f(x) = ? And how do I solve it

The coordinates r(1, -3), s(3, -1) t(5, -7) form what type of polygon? a right triangle an acute triangle an equilateral triangle an obtuse triangle

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

Aline has a slope of . which ordered pairs could be points on a parallel line? check all that apply. (-8, 8) and (2, 2) (-5, -1) and (0, 2) (-3, 6) and (6, -9) (-2, 1) and (3,-2) (0, 2) and (5,5)