At 6: 00 p. m., the temperature was 55°f. at 11: 00 p. m. that same evening, the
temperature was 40°f. what real number represents the average change in
temperature per hour?
me

3

Step-by-step explanation:

11:00 pm - 6:00pm = 5 hour span

55-40=15 decreased each hour

5 divided by 15

0.3 = 3

3 x 5 = 15

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