The level of water in a dam was decreasing by 20% each day. If the level of water was 1500cm, what was the level after two days?

And we know that the level is decreasing 20% each day so then we can use the following model for the problem

Where t represent the number of days and L the level for this case we want to fnd the level after two days so then t =2 and replacing we got:

Step-by-step explanation:

For this case we know that the initial volume of water is:

And we know that the level is decreasing 20% each day so then we can use the following model for the problem

Where t represent the number of days and L the level for this case we want to fnd the level after two days so then t =2 and replacing we got:

entering that problem on the tube might get you an answer

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