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3 years ago

Solve for the variable: 3.5x=32.2 What’s the variable?

Mathematics

1 answer:

kirill115 [55]3 years ago

4 0

Answer:

The variable is x.

The value of the variable is 9.2.

Step-by-step explanation:

The equation shows the variable x multiplied by 3.5 with the result of that multiplication being 32.2. In order to solve for x, you must "undo" that multiplication.

The definitions of the multiplicative inverse and of the multiplication identity element tell you how to do that. The multiplicative inverse of a number is its reciprocal: the multiplicative inverse of 3.5 is 1/3.5. Multiplying a number by its multiplicative inverse gives a result of 1. Here, that means ...

3.5 × (1/3.5) = 1

The property of the multiplicative identity element (1) is that anything multiplied by that is just that thing:

x · 1 = x

So, to solve this equation, you multiply both sides by the multiplicative inverse of 3.5:

3.5x = 32.2

(1/3.5)(3.5)x = (1/3.5)(32)

1x = 9.2 . . . . . carry out the multiplication

x = 9.2 . . . . . . recognize 1x = x

___

You will recognize that multiplying by 1/3.5 is the same as dividing by 3.5. In other words, we solve this equation by dividing it by the coefficient of x.

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4 years ago

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Answer:

Example system with no solution

We're asked to find the number of solutions to this system of equations:

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There is no solution to this system of equations.

Example system with infinite solutions

We're asked to find the number of solutions to this system of equations:

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Interestingly, if we multiply the second equation by -2−2minus, 2, we get the first equation:

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Step-by-step explanation:

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3 years ago

What is the area of an equilateral triangle with perimeter 24 inches?

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2 years ago

A snail can move 1/30 miles in 1/3 hour. How fast does a snail move in miles /hours

bekas [8.4K]

Answer: 1/10 miles/hour

To find how fast a snail moves in miles per hour, we can find the unit rate using a proportion.

The unit rate is the amount per one unit. In this problem, the unit is for one hour. One way to find the unit rate is by using a proportion.

<h2>Proportions</h2>

Proportions look like two fractions set equal to each other with a missing variable to solve.

<h3>State our variables</h3>

let <em>x</em> be the number of miles per hour

<h3>Write a proportion</h3>

The first fraction has a number for the numerator (top) and denominator (bottom), because the question gives us the information. The second fraction has a missing value, <em>x</em>, that we are solving for. We can write <em>x</em> in the numerator.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{x\ mi}{1\ hr}}$

<h2>Solve</h2>

We can solve by finding the scale factor. The scale factor is the number we can multiply the numerator by to find <em>x</em>.

<h3>Find the scale factor</h3>

Start with the proportion.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{x\ mi}{1\ hr}}$

To find the scale factor,

Take the denominator from the fraction with a variable: $1\ hr$
Take the denominator from the fraction that has no variable: $\frac{1}{3}\ hr$
Divide step 1 by step 2 and solve: $1\ hr\ \div\ \frac{1}{3}\ hr = 3$

Our scale factor is <u>3</u>.

<h3>Solve for x</h3>

We can find <em>x</em> by multiplying the numerator in the first fraction by the scale factor. This is because <em>x</em> is also in the numerator.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{(\frac{1}{30}\ mi)*3}{1\ hr}}$

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{\frac{3}{30}\ mi}{1\ hr}}$

Simplify 3/30 by dividing the fraction by 3.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{\frac{1}{10}\ mi}{1\ hr}}$

x = 1/10

∴ a snail moves 1/10 miles per hour.

Learn another way to solve proportions here: brainly.com/question/18437927

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2 years ago

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3 years ago

Read 2 more answers