Which two ratios form a proportion? 3:4 and 6:12
3:4 and 9:15
3:4 and 12:18
3:4 and 15:20

What is the slope of a line that is perpendicular to y = 3x + 1

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

Identify the type of observational study described. a statistical analyst obtains data about ankle injuries by examining a hospital's records from the past 3 years. cross-sectional retrospective prospective