The quotient of a number and -5 increased by 7 is a minimum 1

Please help to answer with working.

dusya [7]

Answer:

When r=0.2, m=0.016g

When m=0.25, r=0.5cm

When r=0.7, m=0.686g

When m=11.664, r=1.8cm

Step-by-step explanation:

General outline of steps for proportionality problems:

Identify the type or proportionality.
Find the proportionality constant using a known input/output pair.
Use the proportionality equation to find other unknowns.

<h3><u>Background on proportionality relationships</u></h3>

There are two main types of proportionality, "direct" and "inverse", and then there are modifications that can be made to them. Several examples are listed below:

<u>Direct proportionality examples</u>

y is directly proportional to x: $y=kx$
y is directly proportional to the square of x: $y=kx^2$
y is directly proportional to the cube of x: $y=kx^3$

<u>Inverse proportionality examples</u>

y is inversely proportional to x: $y=\dfrac{k}{x}$
y is inversely proportional to the square of x: $y=\dfrac{k}{x^2}$

In each case, irregardless of which type, the two quantities are related with some extra letter "k", called the proportionality constant. Either way, the proportionality constant "k" is always in the numerator, and the quantity is either multiplied to or divided from the proportionality constant "k".

Notice that for direct proportionality, in each case, the equation always ends up as "k times" the quantity.

On the other hand, notice that for inverse proportionality, in each case, the equation always ends up as "k divided by" the quantity.

<h3><u>Step 1. Identify the type or proportionality </u><u>(Setting up our proportionality equation)</u></h3>

The problem says "... the mass, <em>m</em> g, of a sphere is directly proportional to the cube of its radius, <em>r</em> cm...", so our equation will look like $m=kr^3$ .

<h3><u>Step 2. Finding the proportionality constant</u></h3>

To find the proportionality constant for our situation, one must know a full input/output pair. Notice that in the 4th column, $r=1.5$ and $m=6.75$ .

Substituting these values into our equation, we can find "k".

$(6.75)=k(1.5)^3$

$6.75=k*3.375$

$\dfrac{6.75}{3.375}= \dfrac{k*3.375}{3.375}$

$2=k$

So, the proportionality constant for this situation is 2, and our equation for this situation becomes: $m=2r^3$

<h3><u>Step 3. Finding the other inputs/outputs</u></h3>

Now that we know the proportionality constant for this situation, if we have either the input OR the output, we can solve for the other unknown.

$m=2r^3$

$m=2(0.2)^3$

$m=2(0.008)$

$m=0.016$

Recall the the question said that the mass, m, was measured in grams, and the radius, r, was measured in centimeters. So, if the radius is 0.2cm, then the mass of the sphere would be 0.016g.

$m=2r^3$

$(0.25)=2r^3$

$\dfrac{0.25}{2}=\dfrac{2r^3}{2}$

$0.125=r^3$

$\sqrt[3]{0.125} = \sqrt[3]{r^3}$

$0.5=r$

So, if the mass of the sphere were 0.25g, the radius of the sphere would be 0.5cm.

$m=2r^3$

$m=2(0.7)^3$

$m=2(0.343)$

$m=0.686$

So, if the radius is 0.7cm, then the mass of the sphere would be 0.686g.

$m=2r^3$

$(11.664)=2r^3$

$\dfrac{11.664}{2}=\dfrac{2r^3}{2}$

$5.832=r^3$

$\sqrt[3]{5.832} = \sqrt[3]{r^3}$

$1.8=r$

So, if the mass of the sphere were 11.664g, the radius of the sphere would be 1.8cm.

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Angles of a triangle

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Answer: A= 1/2bh

The b is for base and the h is for height

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I need 7/5 renamed to a fraction

Setler79 [48]

Answer:

Step-by-step explanation:

the simpliest form is $1\frac{2}{5}$

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pamela wants to buy a new mercedes.The mercedes wheel has a radius of 35', what is the area of the mercedes wheel?

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Pamela wants to buy a new mercedes.The mercedes wheel has a radius of 35', what is the area of the mercedes wheel? the answer would be 3848.45

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If the leading coefficient of a polynomial function is positive, the graph will go

Greeley [361]

Step-by-step explanation:

the leading coefficient means the coefficient (factor) of the term with the highest exponent of the variable (typically x).

with sufficiently large values of this variable (x - going far enough to the right) this term will "win" in value against any other term of the polynomial expression.

and therefore the sign of its factor (coefficient) will determine, if the curve will go up or down.

a positive factor (coefficient) will make the value of this term and therefore of the whole polynomial larger and larger, making the curve going up to +infinity.

a negative factor (coefficient) will make the value of this term and therefore of the whole polynomial smaller and smaller (more negative and more negative), making the curve going down to -infinity.

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