Find the value of Tan^-1 sqrt3/3

Consider the system: y = 3x + 5 y = ax + b what values for a and b make the system inconsistent? what values for a and b make the system consistent and dependent? explain

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

Agraph of a trapezoid can have diagonals with slopes that are negative reciprocals and two pairs of adjacent sides that are congruent, true or false, and why