An exterior angle of a triangle is formed by extending one side of a triangle. There are two exterior angles at each vertex of a triangle, as shown for ZXY in the figures at the right. Why are the two exterior angles at the same vertex congruent?

Mr. walker gave his class the function f(x) = (x + 3)(x + 5). four students made a claim about the function. each student’s claim is below. jeremiah: the y-intercept is at (15, 0). lindsay: the x-intercepts are at (–3, 0) and (5, 0). stephen: the vertex is at (–4, –1). alexis: the midpoint between the x-intercepts is at (4, 0). which student’s claim about the function is correct?

Use complete sentences to differentiate between a regular tessellation, and a pure tessellation. be sure to include specific types of polygons in your explanation.

Find the distance between (7,-6) and (-3,-9)