All categories

3 years ago

1

Mathematics

1 answer:

AysviL [449]3 years ago

8 0

Answer:

I think a b c and d but I really dont know what you are asking

You might be interested in

Factor $-2.8$ out of $-16.8m-11.2$ .

Talja [164]

-2.8(6m + 4) that is the answer

7 0

2 years ago

A 13-ft ladder is leaning against a house when its base starts to slide away. By the time the base is 5 ft from the house, the

lord [1]

Answer:

a. -5 ft per sec

b. 59.5 ft² per sec

Step-by-step explanation:

a. Suppose l represents the ladder, x represents the height of the top of ladder from the base of house and y represents the distance of base of ladder from the base of house.

By the Pythagoras theorem,

$l^2 = x^2 + y^2------(1)$

Differentiating with respect to t ( time ),

$2l\frac{dl}{dt} = 2x \frac{dx}{dt}+2y\frac{dy}{dt}$

But, height of ladder, l = 13 ft = constant,

$\implies \frac{dl}{dt}=0$

$\implies 0= 2x \frac{dx}{dt}+2y\frac{dy}{dt}-----(2)$

We have,

y = 5, $\frac{dy}{dt}=12\text{ ft per sec}$ ,

Again by equation (1),

$13^2 = x^2 + 5^2\implies 169 = x^2 + 25\implies 169 - 25 = x^2\implies 144 = x^2\implies x = 12\text{ ft}$

From equation (2),

$0 = 2(12) \frac{dx}{dt} + 2(12)(5)$

$0= 24\frac{dx}{dt}+120$

$-120 =24\frac{dx}{dt}$

$\implies \frac{dx}{dt}=-\frac{120}{24}=-5\text{ ft per sec}$

Hence, the rate of change of the height of the top of the ladder is -5 ft per sec.

b. Now area of the triangle = 1/2 × base × height

$\implies A = \frac{1}{2}\times y\times x$

Differentiating with r. t. t,

$\frac{dA}{dt}=\frac{1}{2}(y\frac{dx}{dt}+x\frac{dy}{dt})$

$= \frac{1}{2}(5(-5) + 12(12))$

$=\frac{1}{2}(-25 + 144)$

$=\frac{119}{2}$

= 59.5 ft² per sec

Hence, area of the triangle is changing with the rate of 59.5 ft per sec.

7 0

4 years ago

please help... The triangle represents a cross section from a 3D prism. Draw or describe the 3D prism that produced this cross s

Mamont248 [21]

This creates a cone! :) the formula for volume of it is 1/3 pi R^2 (h) just in case!

4 0

2 years ago

Can the sum of two numbers be equal to 2 explain why or why not

Vlada [557]

Answer:

no, because they need a 1 or a fraction yo be a mixed number..... I hope that helps

Step-by-step explanation:

6 0

4 years ago

If one pair of opposite sides of a quadrilateral is both congruent and____ then the quadrilateral is a parallelogram then the

never [62]

Answer:

parallel

a quadrilateral can be a parallelogram only and only if pair of opposite sides are equal and parallel.

5 0

2 years ago