SOLUTION: The value of a stock, A(x), over a year long period decreased and then increased according to the
quadratic function 𝐴(𝑥) = 0.75𝑥
2 − 6𝑥 + 20, where x represents t
Question 1162485: The value of a stock, A(x), over a year long period decreased and then increased according to the
quadratic function 𝐴(𝑥) = 0.75𝑥
2 − 6𝑥 + 20, where x represents the number of months passed since
you invested. The value of another stock, B(x), increased linearly according to the equation
𝐵(𝑥) = 2.75𝑥 + 1.50 over the same year. After how long are both stocks worth the same amount? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! Set the two equal
0.75x^2-6x+20=2.75x+1.50
0.75x^2-8.75x+18.5=0
x=(1/1.5)(8.75 +/- sqrt (76.56-55.5)); sqrt term is 4.59
the larger root is later in time and is (2/3)(20.22)=8.89 months
(the earlier intersection was at 2.77 months)
can also multiply through by 4 to get 3x^2-35x+74
