Write the rule for finding the coordinates of a point’s 90⁰ clockwise rotation about the origin.

The graph below shows a system of equations: Draw a line labeled y equals minus x plus 5 by joining the ordered pairs 0, 5 and 5

Nina [5.8K]

IM NEW HERE I THINK ITS 677

7 0

3 years ago

Which expression is equivalent to a2 + 2a – 8?

marshall27 [118]

Answer:

D

Step-by-step explanation:

(a+4)(a-2)=a^2+2a-8

a*a=a^2

a*(-2)=-2a

a*4=4a

4*(-2)=-8

a^2-2a+4a-8=a^2+2a-8

4 0

3 years ago

Water is leaking out of an inverted conical tank at a rate of 6800 cubic centimeters per min at the same time that water is bein

ivanzaharov [21]

Answer:

1508527.582 cm³/min

Step-by-step explanation:

The net rate of flow dV/dt = flow rate in - flow rate out

Let flow rate in = k. Since flow rate out = 6800 cm³/min,

dV/dt = k - 6800

Now, the volume of a cone V = πr²h/3 where r = radius of cone and h = height of cone

dV/dt = d(πr²h/3)/dt = (πr²dh/dt)/3 + 2πrhdr/dt (since dr/dt is not given we assume it is zero)

So, dV/dt = (πr²dh/dt)/3

Let h = height of tank = 12 m, r = radius of tank = diameter/2 = 3/2 = 1.5 m, h' = height when water level is rising at a rate of 21 cm/min = 3.5 m and r' = radius when water level is rising at a rate of 21 cm/min

Now, by similar triangles, h/r = h'/r'

r' = h'r/h = 3.5 m × 1.5 m/12 m = 5.25 m²/12 m = 2.625 m = 262.5 cm

Since the rate at which the water level is rising is dh/dt = 21 cm/min, and the radius at that point is r' = 262.5 cm.

The net rate of increase of water is dV/dt = (πr'²dh/dt)/3

dV/dt = (π(262.5 cm)² × 21 cm/min)/3

dV/dt = (π(68906.25 cm²) × 21 cm/min)/3

dV/dt = 1447031.25π/3 cm³

dV/dt = 4545982.745/3 cm³

dV/dt = 1515327.582 cm³/min

Since dV/dt = k - 6800 cm³/min

k = dV/dt - 6800 cm³/min

k = 1515327.582 cm³/min - 6800 cm³/min

k = 1508527.582 cm³/min

So, the rate at which water is pumped in is 1508527.582 cm³/min

5 0

3 years ago

50% of babies are born female.Olive wants to find the probability 20 or more of the 50 babies born today were female. If we use

Anna [14]

Answer:

D. Keep track of the number of heads flipped in 50 flips. These represent the number of females born today. Repeat this 200 times.

3 0

3 years ago

Sheila, janice, and katen, working together at the same rate, can complete a job in 3 1/3 days. Working at the same rate, how mu

pychu [463]

Answer:

Janice and Karen could do in 1 day:

20% of the job.

Step-by-step explanation:

To identify how much of the job could janice and caren do in 1 day, first, we must find how much of the job make just 1 person at the same rate:

If three persons make a job in 3 1/3 days, 1 person make the job in x:

3 persons ⇒ 3 1/3 days or 10/3 days
1 person ⇒ x

Then:

$x=\frac{1 person*\frac{10}{3}days }{3 persons}$ (we cancel the unit "persons")
$x=\frac{\frac{10}{3}days }{3}$
x = 10 days

Just a person would need 10 days to complete a job, now, we're gonna divide this value in 2 to obtain the time that need two persons to complete a job:

Time to complete a job between 2 persons = $\frac{10}{2}days$
Time to complete a job between 2 persons = 5 days

How two persons need 5 days to complete a job (in this case, the two persons are Janice and Karen), we can make a simple rule of three to obtain the percentage made in 1 day:

5 days ⇒ 100% of a job
1 day ⇒ x

Then:

$x=\frac{1*100}{5}$ (you can use the % if you want, the result is the same)
$x=\frac{100}{5}$
$x=20$

As you can see, Janice and Karen just in a day could do 20% of the job.

3 0

3 years ago