How do you decide whether substitution is the best method to solve a system in three variables?

What is the ratio for the surface areas of the cones shown below, given that they are similar and that the ratio of their radii and altitudes is 2: 1? submit

What is the slope of the line passing through the points (-5, 7) and (-3,5)?

Kilgore trout creates a new scale to diagnose depression. however, his scale only assesses one symptom of depression while ignoring others. which of the following is his new scale most likely lacking? a) test-retest reliability b) discriminant validity c) criterion validity d) alternate-forms reliability e) content validity f) none of the above