# Solving Math Equations: Module 4

616 Words Feb 4th, 2018 2 Pages
Rensvold)
A company's costs, in millions of dollars, are given by the equation, C = x2 3x 27, where x is the number of items sold, in thousands. What are the costs when 1,000 items are sold? 1,500 items? (Hint: If the number of items sold is 1000, then x=1.
C = 12 3(1) 27 C = 1.52 - 3(1.5) - 27
= 1 -3 27 = 2.25 4.5 - 27
C = -29 C = -29.25
\$29 million \$29,250,000
A company's costs, in millions of dollars, are given by the equation, C = x2 3x 27, where x is the number of items sold, in thousands. How many items must be sold for the costs to be zero?
0 = x2 -3x 27
3 Â± (-3)2 -4(1 x -27) / 2(1)
3 Â± 9+108 / 2
3 Â± 117 / 2
6.9
Approximately 6,900 items
An object's height, in meters, when thrown vertically from the ground at a velocity of 80 m/s is given by the equation H = -4.9t2 + 80t. Ignoring wind resistance, what is the height of the ball after 2 seconds? 3 seconds? 10 seconds?
H = -4.9(2)2 + 80(2) H = -4.9(3)2 + 80(3) H = -4.9(10)2 + 80(10)
-4.9(4) + 160 -4.9(9) + 240 -4.9(100) + 800
-19.6 + 160 -44.1 + 240 -490 + 800
140.4 meters 195.9 meters 310 meters
An object's height, in meters, when thrown vertically from the ground at a velocity of 80 m/s is given by the equation H = -4.9t2 + 80t. Ignoring wind resistance, how many seconds will it take the object to return to the ground? In other words, when is H = 0?
0 = -4.9t2 + 80t
0 = -4.9t + 80
-80 = -4.9t t = 16.326 seconds
The distance d traveled by an object…