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3 years ago

#13 please help I don’t know how to do it

Mathematics

1 answer:

Kruka [31]3 years ago

8 0

2x+5x-4=31
7x-4=31
7x=35
X=5

ST=5x-4= 5.5-4=25-4=21

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The volume V of an ice cream cone is given by V = 2 3 πR3 + 1 3 πR2h where R is the common radius of the spherical cap and the c

Nuetrik [128]

Answer:

The change in volume is estimated to be 17.20 $\rm{in^3}$

Step-by-step explanation:

The linearization or linear approximation of a function $f(x)$ is given by:

$f(x_0+dx) \approx f(x_0) + df(x)|_{x_0}$ where $df$ is the total differential of the function evaluated in the given point.

For the given function, the linearization is:

$V(R_0+dR, h_0+dh) = V(R_0, h_0) + \frac{\partial V(R_0, h_0)}{\partial R}dR + \frac{\partial V(R_0, h_0)}{\partial h}dh$

Taking $R_0=1.5$ inches and $h=3$ inches and evaluating the partial derivatives we obtain:

$V(R_0+dR, h_0+dh) = V(R_0, h_0) + \frac{\partial V(R_0, h_0)}{\partial R}dR + \frac{\partial V(R_0, h_0)}{\partial h}dh\\V(R, h) = V(R_0, h_0) + (\frac{2 h \pi r}{3} + 2 \pi r^2)dR + (\frac{\pi r^2}{3} )dh$

substituting the values and taking $dx=0.1$ and $dh=0.3$ inches we have:

$V(R_0+dR, h_0+dh) =V(R_0, h_0) + (\frac{2 h \pi r}{3} + 2 \pi r^2)dR + (\frac{\pi r^2}{3} )dh\\V(1.5+0.1, 3+0.3) =V(1.5, 3) + (\frac{2 \cdot 3 \pi \cdot 1.5}{3} + 2 \pi 1.5^2)\cdot 0.1 + (\frac{\pi 1.5^2}{3} )\cdot 0.3\\V(1.5+0.1, 3+0.3) = 17.2002\\\boxed{V(1.5+0.1, 3+0.3) \approx 17.20}$

Therefore the change in volume is estimated to be 17.20 $\rm{in^3}$

4 0

3 years ago

What is the center of the following circle?<br> (x + 7)2 + (y - 9)2 = 16

Cerrena [4.2K]

Answer:

Step-by-step explanation:

hello :

the center is : (-7 , 9)

6 0

3 years ago

NEED HELP ASAP PLEASE!! The provided diagram of triangle ABC will help you to prove that the base angles of an isosceles triangl

Lunna [17]

Answer: The proof is mentioned below.

Step-by-step explanation:

Here, Δ ABC is isosceles triangle.

Therefore, AB = BC

Prove: Δ ABO ≅ Δ ACO

In Δ ABO and Δ ACO,

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Thus, By ASA postulate of congruence,

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3 years ago

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Zigmanuir [339]

Answer:

(2 , 30) & (4, 60)

Step-by-step explanation:

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3 years ago

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Answer:

19.44 hours, about 19 hours 26 minutes

Step-by-step explanation:

The exponential equation that describes your caffeine level can be written as ...

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10 = 120(0.88^t)

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log(1/12) = t·log(0.88) . . . take logarithms

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3 years ago