Triangle ABC is a right triangle. If side AC = 7 and side BC = 10, what is the measure of side AB?

The liquid base of an ice cream has an initial temperature of 86°C before it is placed in a freezer with a constant temperature

Karolina [17]

The temperature of the ice cream 2 hours after it was placed in the freezer is 37.40 °C

From Newton's law of cooling, we have that

$T_{(t)}= T_{s}+(T_{0} - T_{s})e^{kt}$

Where

$(t) = \ time$

$T_{(t)} = \ the \ temperature \ of \ the \ body \ at \ time \ (t)$

$T_{s} = Surrounding \ temperature$

$T_{0} = Initial \ temperature \ of \ the \ body$

$k = constant$

From the question,

$T_{0} = 86 ^{o}C$

$T_{s} = -20 ^{o}C$

∴ $T_{0} - T_{s} = 86^{o}C - -20^{o}C = 86^{o}C +20^{o}C$

$T_{0} - T_{s} = 106^{o} C$

Therefore, the equation $T_{(t)}= T_{s}+(T_{0} - T_{s})e^{kt}$ becomes

$T_{(t)}=-20+106 e^{kt}$

Also, from the question

After 1 hour, the temperature of the ice-cream base has decreased to 58°C.

That is,

At time $t = 1 \ hour$ , $T_{(t)} = 58^{o}C$

Then, we can write that

$T_{(1)}=58 = -20+106 e^{k(1)}$

Then, we get

$58 = -20+106 e^{k(1)}$

Now, solve for $k$

First collect like terms

$58 +20 = 106 e^{k}$

$78 =106 e^{k}$

Then,

$e^{k} = \frac{78}{106}$

$e^{k} = 0.735849$

Now, take the natural log of both sides

$ln(e^{k}) =ln( 0.735849)$

$k = -0.30673$

This is the value of the constant $k$

Now, for the temperature of the ice cream 2 hours after it was placed in the freezer, that is, at $t = 2 \ hours$

From

$T_{(t)}=-20+106 e^{kt}$

Then

$T_{(2)}=-20+106 e^{(-0.30673 \times 2)}$

$T_{(2)}=-20+106 e^{-0.61346}$

$T_{(2)}=-20+106\times 0.5414741237$

$T_{(2)}=-20+57.396257$

$T_{(2)}=37.396257 \ ^{o}C$

$T_{(2)} \approxeq 37.40 \ ^{o}C$

Hence, the temperature of the ice cream 2 hours after it was placed in the freezer is 37.40 °C

Learn more here: brainly.com/question/11689670

6 0

3 years ago

Read 2 more answers

The picture shows

mixer [17]

Answers:

a) 693 sq cm (approximate)
b) 48 sq cm (exact)

============================================================

Explanation:

Part (a)

A regular triangular pyramid, aka regular tetrahedron, has all four triangles that are identical copies of one another. They are congruent triangles. This will apply to part (b) as well.

To find the area of one of the triangles, we'll use the formula

A = 0.25*sqrt(3)*x^2

where x is the side length. This formula applies to equilateral triangles only.

In this case, x = 20, so

A = 0.25*sqrt(3)*x^2

A = 0.25*sqrt(3)*20^2

A = 173.20508 approximately

That's the area of one triangle, but there are four total, so the entire area is about 4*173.20508 = 692.82032 which rounds to 693 sq cm.

The units "sq cm" can be written as "cm^2".

----------------------------

Part (b)

We'll use the same idea as part (a). But the formula to find the area of one triangle is much simpler.

The area of one of the triangles is A = 0.5*base*height = 0.5*6*4 = 12 sq cm.

So the area of all four triangles combined is 4*12 = 48 sq cm

This area is exact.

The area of each 2D flat net corresponds exactly to the surface area of each 3D pyramid. This is because we can cut the figure out and fold along the lines to form the 3D shapes.

7 0

3 years ago

The Clark family must pay $2,820 in property tax on their home this year. The house payment $752 per month. What is their paymen

Harlamova29_29 [7]

It's actually easier than it seems. if the tax is paid in equal payments every month and the total throughout a year (12 months) is $2,820, you have to find out how much they pay every month
so divide the total by the number of months
2,820/12=235
they pay $235 in taxes every month
to find out the total of the taxes and the house payment, just add the monthly tax and the monthly house payment.
235+752
and your answer is the sum

8 0

4 years ago

Read 2 more answers

There is a regular dodecahedron with all the points connected to each other. What is the area if each of the shales formed if th

tamaranim1 [39]

Answer:

18581.16

Step-by-step explanation:

The area of each of the shale can be calculated as

distance between each point = x

The area of the regular Dodecahedron

A = $\sqrt[3]{25+10\sqrt{5} } a^{2}$