Joe bought 15 items for $135. If the 15 items consisted of notebooks that cost $4.50 each and calculators that cost $12.00 each, how many of each did he buy?

Aregression was run to determine if there is a relationship between hours of tv watched per day (x) and number of situps a person can do (y). the results of the regression were: y=ax+b a=-0.662 b=30.418 r2=0.703921 r=-0.839

Is this a polynomial function? i need to know asap

Arectangle has a width of 5 cm and a length of 10 cm. if the width is increased by 3, how does the perimeter change?