If (x - 3) and (x + 7) are the factors of the trinomial x2 + ax – 21, what is the value of a?
A.)-3
Б.)-4
C.)7
Д.)4

What is the volume of a rectangular prism if the length is 10.4 mm the width is 5 mm in the height is 8 mm

List the sides of δrst in ascending order (shortest to longest) if: m∠r =x+28°, m∠s = 2x+16°, and m∠t = x+12

Aretha wanted to gather data about the cost of local bowling leagues in her area. she plotted the data and determined that the average bowling league costs consist of a one-time registration fee and a monthly fee modeled by the equation y = 15x + 20. identify and interpret the y-intercept in this model. the y-intercept is 20. this is the cost per month. the y-intercept is 20. this is the cost of registration. the y-intercept is 15. this is the cost of registration. the y-intercept is 15. this is the cost per month.