The bangor coat factory found that the number of coats sold n varies directly as their advertising budget a and inversely as the price of each coat p. the bangor coat factory sold 10,800 coats when $30,000 was spent on advertising and the price of a coat was set at $50. determine the number of coats sold when the amount spent on advertising is increased to $70,000

a) 3888 coats b) 24480 c) 1400 d) 25200

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

the formula of a slope:

we have the points (-2, 7) and (2, 3). substitute: