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4 years ago

Which of the following numbers is irrational? (1 point)

Mathematics

1 answer:

eimsori [14]4 years ago

4 0

Answer:

The correct answer is D. π

Step-by-step explanation:

Let's recall that rational numbers are those that can be written as a ratio or fraction of two integers. Quite the opposite, irrational numbers can't be written as a ratio or fraction of two integers.

Upon saying that we have:

A. A fraction with numerator negative 15 and denominator 4 is a rational number because we can represent it: -15/4

B. A fraction with numerator negative 7 and denominator 9 is a rational number because we can represent it: -7/9

C. √4 is a rational number because we can represent it: 2 or 2/1

D. π is the most known irrational number because we can't represent it as a ratio or fraction: 3.14159265358979....and more can't be written as a ratio or fraction.

The correct answer is D. π

You might be interested in

What is the difference 7/78 - 3 1/4=

ZanzabumX [31]

here
7 7/8
= [ (8*7) + 7 ] / 8
= (56 + 7) / 8
=63 / 8

similarly,
3 1/4
=[ (4*3) + 1] / 4
= (12 + 1) / 4
= 13/4

----------------------------
now put the values
7 7/8 - 3 1/4
= 63/8 - 13/4
here, take LCM of 8 & 4 which is 8.
now,
[ (1*63) - (2 * 13) ] / 8
= (63 - 26) / 8
= 37/8
= 4 5/8........................[ here, divide 37 by 8 which gives reminder as 5 and divisible value as 4 ]

3 0

3 years ago

Read 2 more answers

17. ralph is 3 times as old as sarah. in 4 years ralph will only be twice as old as sara will be then. find ralph’s age now.

spin [16.1K]

Answer:

Sara is now 4, will be 8 in 4 years. Ralph is now 12, will be 16 in 4 years.

7 0

3 years ago

Help with 21 would be much appreciated.

umka2103 [35]

Answer:

$\large\boxed{x=2\sqrt{21}\ and\ y=4\sqrt3}$

Step-by-step explanation:

Look at the picture.

ΔADC and ΔCDB are similar. Therefore the sides are in proportion:

$\dfrac{AD}{CD}=\dfrac{CD}{DB}$

We have

$AD=14-8=6\\CD=y\\DB=8$

Substitute:

$\dfrac{6}{y}=\dfrac{y}{8}$ cross multiply

$y^2=(6)(8)$

$y^2=48\to y=\sqrt{48}\\\\y=\sqrt{16\cdot3}\\\\y=\sqrt{16}\ cdot\sqrt3\\\\\boxed{y=4\sqrt3}$

For x use the Pythagorean theorem:

$x^2=6^2+(4\sqrt3)^2\\\\x^2=36+48\\\\x^2=84\to x=\sqrt{84}\\\\x=\sqrt{4\cdot21}\\\\x=\sqrt4\cdot\sqrt{21}\\\\\boxed{x=2\sqrt{21}}$

3 0

3 years ago

To estimate the height of a house Katie stood a certain distance from the house and determined that the angle of elevation to th

Nata [24]

the height of the house is $408ft$ .

Step-by-step explanation:

Here we have , To estimate the height of a house Katie stood a certain distance from the house and determined that the angle of elevation to the top of the house was 32 degrees. Katie then moved 200 feet closer to the house along a level street and determined the angle of elevation was 42 degrees. We need to find What is the height of the house . Let's find out:

Let y is the unknown height of the house, and x is the unknown number of feet she is standing from the house.

Distance of house from point A( initial point ) = x ft

Distance of house from point B( when she traveled 200 ft towards street = x-200 ft

Now , According to question these scenarios are of right angle triangle as

At point A

⇒ $Tan32 =\frac{Perpendicular}{Base}= \frac{y}{x}$