can someone me with this one? it’s very difficult too me

The equation is C = 20t^2 + 135t + 3050

You are told the total number of cars sold is 15000.

Replace c with 15,000 and solve for t:

15000 = 20t^2 + 135t + 3050

Subtract 15000 from both sides:

0 = 20t^2 + 135t - 11950

Use the quadratic formula to solve for t.

In the quadratic formula -b +/-√(b^2-4(ac) / 2a

using the equation, a = 20, b = 135 and c = -11950

The formula becomes -135 +/- √(135^2 - 4(20*-11950) / (2*20)

t = 21.3 and -28.1

T has to be a positive number, so t = 21.3,

Now you are told t = 0 is 1998,

so now add 21.3 years to 1998

1998 + 21.3 = 2019.3

So in the year 2019 the number of cars will be 15000

question 1: step-by-step explanation:

1/4 of 84 = 84÷4= 21