A triangle has vertices on a coordinate grid at B(-1,2)B(−1,2), C(-1,-2)C(−1,−2), and D(3,-2).D(3,−2). What is the length, in units, of \overline{BC} BC?

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?

Mackenzie needs to determine whether the rectangles are proportional. which process could she use? check all that apply.

Janice determined there were 10 possible outcomes when tossing two coins and spinning a spinner numbered 1 through 6. what is the correct number? what might have been janice's error?