Commutative property of multiplication is two numbers being multiplied either way,example 1x2 = 2x1.
F(x)= 9x^3 + 2x^2 - 5x + 4
g(x)= 5x^3 - 7x + 4
f(x) - g(x)
9x³ + 2x² - 5x + 4 - (5x³ - 7x + 4)
9x³ + 2x² - 5x + 4 - 5x³ +7x - 4
9x³ - 5x³ + 2x² -5x + 7x + 4 - 4
4x³ + 2x² + 2x
Answer:
11 gallons of gas is needed to travel 231 miles.
Step-by-step explanation:
We can set up a proportion for this problem.
<em>For every 62 miles, you use 3 gallons of gas. </em>

Now, let's cross multiply.
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So, you will need about 11 gallons of gas to travel 231 miles.
I'm going to divide number one to 6 parts
1.

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2.

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3.

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4.

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5.

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6.

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because to make the denominator to 100, you need to multiply 10 by 10 which is 100.
and because you multiply 10, you also have to multiply the numerator by 10.
EXAMPLES:

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About 92 days are taken for 90 % of the material to <em>decay</em>.
The mass of radioisotopes (
), measured in milligrams, decreases exponentially in time (
), measured in days. The model that represents such decrease is described below:
(1)
Where:
- Initial mass, in milligrams.
- Current mass, in milligrams.
- Time constant, in days.
In addition, the time constant is defined in terms of half-life (
), in days:
(2)
If we know that
,
and
, then the time required for decaying is:






About 92 days are taken for 90 % of the material to <em>decay</em>.
We kindly invite to check this question on half-life: brainly.com/question/24710827