Help me pleaseeeeeeeeeee

the area of maddies square garden is 450 square feet. she has purchased 92 feet of fence. is this the right amount of fence for

Keith_Richards [23]

Answer:

Not the right amount.

Step-by-step explanation:

A square has 4 sides so 92/4 to divide it evenly is 23.

23 times 23 for the are is 529 which is not equal to 450.

3 0

3 years ago

A tank initially contains 60 gallons of brine, with 30 pounds of salt in solution. Pure water runs into the tank at 3 gallons pe

adoni [48]

Answer:

the amount of time until 23 pounds of salt remain in the tank is 0.088 minutes.

Step-by-step explanation:

The variation of the concentration of salt can be expressed as:

$\frac{dC}{dt}=Ci*Qi-Co*Qo$

being

C1: the concentration of salt in the inflow

Qi: the flow entering the tank

C2: the concentration leaving the tank (the same concentration that is in every part of the tank at that moment)

Qo: the flow going out of the tank.

With no salt in the inflow (C1=0), the equation can be reduced to

$\frac{dC}{dt}=-Co*Qo$

Rearranging the equation, it becomes

$\frac{dC}{C}=-Qo*dt$

Integrating both sides

$\int\frac{dC}{C}=\int-Qo*dt\\ln(\abs{C})+x1=-Qo*t+x2\\ln(\abs{C})=-Qo*t+x\\C=exp^{-Qo*t+x}$

It is known that the concentration at t=0 is 30 pounds in 60 gallons, so C(0) is 0.5 pounds/gallon.

$C(0)=exp^{-Qo*0+x}=0.5\\exp^{x} =0.5\\x=ln(0.5)=-0.693\\$

The final equation for the concentration of salt at any given time is

$C=exp^{-3*t-0.693}$

To answer how long it will be until there are 23 pounds of salt in the tank, we can use the last equation:

$C=exp^{-3*t-0.693}\\(23/60)=exp^{-3*t-0.693}\\ln(23/60)=-3*t-0.693\\t=-\frac{ln(23/60)+0.693}{3}=-\frac{-0.959+0.693}{3}= -\frac{-0.266}{3}=0.088$

5 0

2 years ago

Please hurry! What is the value of the expression when y=3?

lorasvet [3.4K]

Step-by-step explanation:

$= 12 + {4y}^{2} - 7$

$= 12 + {4(3)}^{2} - 7$

$= 12 + 4(9) - 7$

$= 12 + 36 - 7$

$= 48 - 7$

$= 41$

7 0

2 years ago

What is the equation of the line that passes through the point (-2,0) and has a slople of -2

SCORPION-xisa [38]

Answer:

y= -2x-4

Step-by-step explanation:

$(-2,0) = (x_1,y_1) \\ m = - 2$

Substitute values into point slope form

$y - y_1 = m(x - x_1) \\ y - 0 = - 2(x - ( - 2)) \\ y - 0 = - 2(x + 2) \\ y - 0 = - 2x - 4$

$y = - 2x - 4 + 0 \\ y= - 2x - 4$

6 0

3 years ago

What is the distance from<br> 33, 5) to (33, -12)

Snezhnost [94]

Answer:

17

Step-by-step explanation:

so x stays the same, so you look at the y integers and to get to the negatives you have to go down 5 times, then 12 more to get to -12. So 5+12= 17

Hope this helps!!!!

4 0

2 years ago