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3 years ago

Pls help. Evaluate the expression 3.14(a2 + ab) when a = 3 and b = 4. (Input decimals only, such as 12.71, as the answer.)

Mathematics

1 answer:

givi [52]3 years ago

4 0

3.14(3(2) + 3(4))
3.14( 6 + 12)
3.14(18)
=56.52

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What is the difference of the two expressions shown below (3/4X+2)-(1/4x+5). Explain why

Nostrana [21]

Answer:

D. 1/2x - 3

Step-by-step explanation:

(3/4x + 2) - (1/4x + 5) =
3/4x - 1/4x + 2 - 5 =
2/4x - 3 =
1/2x - 3

Correct choice is D

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2 years ago

A tent is in the shape of a triangular prism. The front and back are isosceles triangles with base 6 feet and height 4 feet. The

Pani-rosa [81]

It would be 6+4, which equals 10. Then, subtract 104 ft minus 10 to get 94 ft in depth.

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2 years ago

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In 2018, the population will grow over 700,000.The population of a city in 2010 was 450,000 and was growing at a rate of 5% per

Firlakuza [10]

Answer:

The year is 2020.

Step-by-step explanation:

Let the number of years passed since 2010 to reach population more than 7000000 be 'x'.

Given:

Initial population is, $P_0=450,000$

Growth rate is, $r=5\%=0.05$

Final population is, $P=700,000$

A population growth is an exponential growth and is modeled by the following function:

$P=P_0(1+r)^x$

Taking log on both sides, we get:

$\log(P)=\log(P_0(1+r)^x)\\\log P=\log P_0+x\log (1+r)\\x\log (1+r)=\log P-\log P_0\\x\log(1+r)=\log(\frac{P}{P_0})\\x=\frac{\log(\frac{P}{P_0})}{\log(1+r)}$

Plug in all the given values and solve for 'x'.

$x=\frac{\log(\frac{700,000}{450,000})}{\log(1+0.05)}\\x=\frac{0.192}{0.021}=9.13\approx 10$

So, for $x > 9.13$ , the population is over 700,000. Therefore, from the tenth year after 2010, the population will be over 700,000.

Therefore, the tenth year after 2010 is 2020.

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2 years ago

A rectangular floor is 7 yards long and 3 yards wide. what is the area of the floor in square feet? be sure to include the corre

mario62 [17]

There are a couple ways to do this, but basically you need to convert the units.

7 yards x 3 ft/yard = 21 feet 
4 yards x 3 ft/yard = 12 feet 
So the area (in sq. ft) will be: 
21 x 12 
= 252 sq. ft. 

Alternatively, you can figure the area in square *yards* and then multiply by 9 sq. ft per sq. yard. 
7 yards x 4 yards x 9 sq. ft/sq. yard 
= 252 sq. ft.

hope this helps :)

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3 years ago

Nikki can make 5 free throws in 8 attempts. If she continues this pattern, how many free throws can she 128 attempts? Show your

konstantin123 [22]

Step-by-step explanation:

80 free throws on 128 attempts

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2 years ago