When could it be most efficient to use the quadratic formula?

Are triangles the congruent? write the congruency statement. what is the congruency that proves they are congruent? what is the perimeter of ∆pqr?

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6

Which diagram shows lines that must be parallel lines cut by transversal?