Why does cross multiplication work / why cross multiplication works

need asap! thank you :)

In two or more complete sentences, formulate how to use technology to calculate the appropriate regression model for the given data. you are not required to find the model, just choose the appropriate regression and explain how to use the technology. (-5,,2.,0.8), (0,-0.5), (2,-1.3), (3,-0.8), (5,2)

Rectangle leg this 11feet and perimeter of 38feet what is the width of the rectangle in feet

Astudent survey asked: "how tall are you (in inches)? " here's the data: 67, 72, 73, 60, 65, 86, 72, 69, 74 give the five number summary. a. median: 73, mean: 70.89, iqr: 5, min: 60, max: 74 b. 60, 66, 72, 73.5, 86 c. 60, 67, 72, 73, 74 d. 0, 60, 70, 89, 74, 100