All categories

3 years ago

Expand and reduce: A = – 3 (5 x – 4) B = (2 x – 8) (4 x – 7)

Mathematics

1 answer:

alina1380 [7]3 years ago

5 0

Answer:

Step-by-step explanation:

You might be interested in

The volume of a cone of radius r and height h is given by V=πr²h³. If the radius and the height both increase at a constant rate

Aloiza [94]

Answer:

The volume of cone is increasing at a rate 1808.64 cubic cm per second.

Step-by-step explanation:

We are given the following in the question:

$\dfrac{dr}{dt} = 12\text{ cm per sec}\\\\\dfrac{dh}{dt} = 12\text{ cm per sec}$

Volume of cone =

$V = \dfrac{1}{3}\pi r^2 h$

where r is the radius and h is the height of the cone.

Instant height = 9 cm

Instant radius = 6 cm

Rate of change of volume =

$\dfrac{dV}{dt} = \dfrac{d}{dt}(\dfrac{1}{3}\pi r^2 h)\\\\\dfrac{dV}{dt} = \dfrac{\pi}{3}(2r\dfrac{dr}{dt}h + r^2\dfrac{dh}{dt})$

Putting values, we get,

$\dfrac{dV}{dt} = \dfrac{\pi}{3}(2(6)(12)(9) + (6)^2(12))\\\\\dfrac{dV}{dt} =1808.64\text{ cubic cm per second}$

Thus, the volume of cone is increasing at a rate 1808.64 cubic cm per second.

5 0

3 years ago

A ladder is leaning on a fence and it reaches up a wall 20 feet high. The fence is 10 feet from the wall and the base of the lad

ElenaW [278]

Easy just subtract 20 and 12 and its 8 the reason how i got that is because the ladder is 20 feet high and it now stands 12 feet on the fence so the fence is only 8 feet PLZ MARK ME BRAINIEST MY ANSWER IS RIGHT i have done the test ur welcome.

5 0

3 years ago

Which expression is equivalent to 3i(9i +15)?<br> - 45 +9i<br> -27 + 452<br> 27 +452<br> 2722 + 452

vaieri [72.5K]

Answer: B. -27+452i

Step-by-step explanation: Simplify the real and imaginary parts of the expression.

Hope this helps you out.

3 0

3 years ago

Find the area of each triangle to the nearest tenth???

pshichka [43]

Answer:C

Step-by-step explanation:

8 0

1 year ago

Help me plz check it

Nikolay [14]

3 1/4 = 3.25

1 mile = 5280

5280 * 3.25 = 17,160

Correct answer is D. 17,160

6 0

3 years ago