A car travels 392 miles in 8 hours (with a constant speed). How far can it travel in 7 hours (with the same speed

8th Grade Math Homework Thursday, January 28th

grin007 [14]

1. -6y
2. 4y+20
3. -6x+6y+4
4. 3x-44
5. •work:
•plug in 4 to the equation
5(2-4)=-10
10-20=-10
-10=-10
•so, yes it is a solution to 5(2-x)
6. •work:
4x+20=0
-20 -20
4x=-20
4x/4=-20/4
x=-5
7. •work:
5x-3=2x-27
-2x -2x
3x-3=-27
+3 +3
3x=-24
3x/3=-24/3
x=-8
8. •work:
6x-8=2x+16
-2x -2x
4x-8=16
+8 +8
4x=24
4x/4=24/4
x=6
9. •work:
12-3x=22+2x
-2x -2x
12-5x=22
-12 -12
-5x=10
-5x/-5=10/-5
x=-2
10. •work:
x+7x-12=-20
8x-12=-20
+12 +12
8x=-8
8x/8=-8/8
x=-1
11.•work:
7x+4-13x=-1+23
-6x+4=-1+23
-6x+4=22
-4 -4
-6x=18
-6x/-6=18/-6
x=3
here you go! hope this helped!! :)

5 0

2 years ago

1. The function of lenses is based on the law of refraction. A light beam is traveling from the medium 1 where its speed is V1,

masha68 [24]

Answer:

The index of refraction for Medium 2 would be 1.25

Step-by-step explanation:

We have the following data:

Speed of light in Medium 1 = V₁

Speed of light in Medium 2 = V₂

The speed of Light in Medium 2 is related to speed of light in Medium 1 as:

V₂ = 0.8 V₁

Moreover, it is given that Medium 1 is air with index of refraction equal to 1. i.e.

n₁ = 1

We need to find the index of refraction for medium 2. Lets name it is as n₂.

Snell's law related the above mentioned 4 quantities by following relation:

The ratio of indices of refraction of 2 mediums is equivalent to the reciprocal of ratio of phase velocities in those 2 mediums. Mathematically, this can be written as:

$\frac{n_{1}}{n_{2}} = \frac{V_{2}}{V_{1}}$

Substituting the values we have gives us:

$\frac{1}{n_{2}}=\frac{0.8V_{1}}{V_{1}} \\\\\frac{1}{n_{2}}=0.8\\\\ 1=0.8n_{2}\\\\\frac{1}{0.8}=n_{2}\\\\ n_{2}=1.25$

This means, the index of refraction for Medium 2 would be 1.25

3 0

3 years ago

One ball is to be selected from a box containing red, white, blue, yellow, and green balls. If the probability that the selected

ZanzabumX [31]

Answer:

30% probability that it will be yellow, or green

Step-by-step explanation:

The urn has red, white, blue, yellow, and green balls.

Each ball is chosen with the following probabilities:

1/10 = 10% probability it is red

2/5 = 40% probability it is white

1/5 = 20% probability it is blue.

p probability it is yellow or green

What is the probability that it will be yellow, or green

The sum of all probabilities is 100%. So

10 + 40 + 20 + p = 100

p = 30

30% probability that it will be yellow, or green

5 0

3 years ago

Thomas's cat, Rainwright, eats 0.8 cans of food every day. How much will Thomas spend on food in one week if each can costs $1.7

marshall27 [118]

1 week = 7 days
$0.8 \times 7 \times 1.75 \\ = 9.8$

Answer : Thomas spends $9.80 on food in one week.

Hope this helps. - M

3 0

3 years ago

The area of a square is 144cm2.what is the measurement of each side

Dmitry [639]

The area of a square is 144 cm^2. The measurement of each side is 12 cm

<u>Solution:</u>

Given, The area of a square is 144 $cm^2$

We have to find that what is the measurement of each side.

Now, we know that, area of a square = product of side value with another side value.

Let the side value of given square be "s"

Then, <em>Area of square is given as:</em>

$\begin{array}{l}{\text {area of square}=s \times s} \\\\ {\text {Area of square}=s^{2}} \\\\ {144=s^{2}} \\\\ {s=\sqrt{144}} \\\\ {s=\sqrt{12^{2}}}\end{array}$

On cancelling square root and square on right side,we get

s = 12

Hence, the side value of the square is 12 cm.

8 0

3 years ago