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Harlamova29_29 [7]

3 years ago

8

A student reflected four points across the y-axis and recorded his work as sets of ordered pairs. Which set of ordered pairs has

an error?
Original point Reflection across the y-axis
A (6, 8) (-6, 8)
B (1, 1) (-1, 1)
C (0, 3) (0, 3)
D (3, 2) (3, -2)
Set A
Set B
Set C
Set D

1 answer:

kykrilka [37]3 years ago

6 0

The set D has an error.

Step-by-step explanation:

Step 1:

Given set of ordered pairs

A (6, 8) (-6, 8)

B (1, 1) (-1, 1)

C (0, 3) (0, 3)

D (3, 2) (3, -2)

We need to find the set which has an error of incorrect reflection across the y axis.

Step 2 :

When a point is reflected across the y - axis , the value of y in the point (x,y) will be the same, and the sign of the x value will be changed to its opposite

i.e if we have a point (x,y) reflection across y axis will be (-x,y)

Step 3 :

Point A - y is same , sign of x is changed to opposite.

Point B - y is same , sign of x is changed to opposite.

Point C - y is same , x is 0

Point D - y is not same , sign of x is not changed to opposite.

Hence the set D has an error.

Step 4 :

Answer :

The set D has an error.

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Answer:

Volume of smaller canister = 763.02 $cm^3$

Surface area of smaller canister = 466.29 $cm^2$

Volume of larger canister = 6104.16 $cm^3$

Surface area of larger canister = 1865.16 $cm^2$

Volume becomes 8 times by doubling the size and surface area becomes 4 times by doubling the size.

Step-by-step explanation:

Given that :

Diameter of Smaller canister = 9 cm

Height of Smaller canister = 12 cm

Larger canister is double the size of smaller one i.e. height and diameter are doubled.

To find:

Volume and surface area of each canister and their comparison.

Solution:

First of all, let us have a look at the formula of volume and surface area of a cylinder.

Volume, $V=\pi r^2h$

Surface Area, $A=2\pi r^2+ 2\pi rh$

where r and h are the radius and height of the cylinder respectively.

Radius is half of diameter.

Radius of smaller canister is given by:

$r_1 = \dfrac{9}{2} = 4.5\ cm$

Height, $h_1 =12\ cm$

Volume, $V_1=\pi (4.5)^2 \times 12 = 763.02\ cm^3$

Surface Area, $A_1 = 2 \pi \times 4.5 ^2 + 2\pi\times 4.5 \times 12 = 466.29 \ cm^2$

Now, Diameter / Radius and height of larger canister are doubled of smaller one.

Radius of larger canister is given by:

$r_2 = \dfrac{9}{2} \times 2 = 9 cm$

Height, $h_2 =12\times 2 = 24\ cm$

Volume, $V_2=\pi (9)^2 \times 24 = 6104.16\ cm^3$

Surface Area, $A_2 = 2 \pi \times 9 ^2 + 2\pi\times 9\times 24= 1865.16 \ cm^2$

Comparing the results, we can easily see that:

$V_2 = 8 \times V_1\\A_2 = 4 \times A_1$

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4 years ago

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Part 1:

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The square root of 81 is 9. We have to find the square root bc we know it is a square.

Part 2:

The hypotenuse (or diagonal) is c.

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$a^{2} + {b}^{2} = {c}^{2}$
you would know that 9 is a and b.

${9}^{2} + {9}^{2} = {c}^{2}$
We know that
${9}^{2} = 81$
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$81 + 81 = 162$
81 and 81 make 162.

So you know ...

${c}^{2} = 162$
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$\sqrt{162} = 12.73$
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You can write your answer as

$about \: 12.73 cm$
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Let S be the sample space for the experiment of choosing a piece.

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Answer:

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