-.1 Vusi sets out for a 40 kilometre run. After he runs for two hours he injures
his ankle. He takes an hour to walk the rest of the way. If he injured
himself after he had run 16 kilometres, he would have taken four hours to
complete the distance. Determine the average speed in kilometres per hour
at which Vusi ran.

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

answer: 1475

step-by-step explanation:

becuase you have to know what they are asking you