All categories

3 years ago

Answer as many as possible please need work for brainilist

Mathematics

1 answer:

zysi [14]3 years ago

6 0

Answer:

1. 18x + 35y = 598

x + y = 20

Isolate a variable in the second equation:

y = -x + 20

Plug y back into the first equation

18x + 35(-x + 20) = 598

18x - 35x + 700 = 598

-17x +700 = 598

-17x = -102

x = 6

You carpool 6 days of the 20

6 + y = 20

y = 14

You ride the bus 14 days of the 20

2. 4.50n + 3p = 252

p = 2n

Substitute p into the first equation

4.50n + 3(2n) = 252

4.50n + 6n = 252

10.5n = 252

n = 24

They sold 24 cans of nuts

p = 2(24)

p = 48

They sold 48 boxes of popcorn

The group sold, in total, 24 + 48 = 72 cans of nuts and boxes of popcorn.

3. x - y = 3

x + y = 8

Isolate a variable

x = y + 3

(y + 3) + y = 8

2y + 3 = 8

2y = 5

y = 2.5

The average speed with wind is 2.5 mph

x - 2.5 = 3

x = 5.5

The average speed without wind is 5.5mph

4. x + 8y = 22.8

x + 6y = 18.6

Isolate

x = -8y + 22.8

Substitute

(-8y + 22.8) + 6y = 18.6

-2y + 22.8 = 18.6

-2y = -4.2

y = -2.1

The gas costs $2.10 per gallon

x + 8(2.1) = 22.8

x + 16.8 = 22.8

x = 6

The cost of the car was is $6.

5. Cost = 9.99 + 2.49x

Cost = 20.49 + 1.79x

To find which one is better, we need to set them equal to each other at first.

9.99 + 2.49x = 20.49 + 1.79x

9.99 + 0.70x = 20.49

0.70x = 10.5

x = 15

So, they cost the same at 15 rentals.

To find which one is the better deal let's see how much both cost after 16 rentals.

Cost = 9.99 + 2.49(16)

= 49.83

Cost = 20.49 + 1.79(16)

= 49.13

Therefore, Main Street is the better deal because after the equilibrium Main Street costs less than Big Video.

6. x + y = 15

.25x + .05y = 2.75

Isolate

x = -y + 15

Solve

.25(-y + 15) + .05y = 2.75

-.25y + 3.75 + .05y = 2.75

-0.2y + 3.75 = 2.75

-0.2y = -1

y = 5

There are 5 nickels

x + 5 = 15

x = 10

There are 10 quarters

7. x + y = 26

x + .25y = 17

Isolate

x = -y + 26

Substitute

(-y + 26) + .25y = 17

-0.75y + 26 = 17

-0.75y = -9

y = 12

There are 12 quarters in his pocket

x + 12 = 26

x = 14

There are 14 dollars

I hope this helps!!

- Kay :)

You might be interested in

Please help me with this question

vichka [17]

Write the ratio out.

Number of hands Betty won : Number of hands Adam won

5:20

Both can be simplified by the common factor of 5.

1:4 is the solution.

5 0

3 years ago

Kathleen and Arnob both run from the park entrance along a loop. Kathleen starts walking from the park entrance and gets a 5-mil

Ilia_Sergeevich [38]

For this case, the first thing we must do is define variables.

We have then:

x: time in minutes

y: distance traveled.

We then have the following equations:

For Kathleen:

$y = (\frac{1}{15}) x + 5$

For Arnob:

$y = (\frac{2}{15}) x$

By the time Arnob reaches Kathleen we have:

$(\frac{1}{15}) x + 5 = (\frac{2}{15}) x$

From here, we clear the value of x.

We have then:

$(\frac{2}{15}) x - (\frac{1}{15}) x = 5$

$(\frac{1}{15}) x = 5\\x = (15) * (5)\\x = 75 min$

Answer:

it takes Arnob to catch up to Kathleen 75 minutes:

d. 75

5 0

3 years ago

Read 2 more answers

It will take five builders 62 days to complete a particular project. At this rate, how long would the project take if there were

Lena [83]

Answer:

2 builder complete work = 155 days

Step-by-step explanation:

Given:

5 builder complete work = 62 days

So,

1 builder complete work = 62 days × 5

if,

2 builder complete work = [62 days × 5] / 2

2 builder complete work = 155 days

6 0

3 years ago

Student Produced Response - Calculator

faltersainse [42]

Answer:

$\dfrac{a}{b}=0.75$ .

Step-by-step explanation:

If two equations $a_1x+b_1y+c_1=0$ and $a_2x+b_2y+c_2=0$ has infinitely many solutions, then

$\dfrac{a_1}{a_2}=\dfrac{b_1}{b_2}=\dfrac{c_1}{c_2}$

The given equations are

$ax+by=10$

$3x+4y=20$

It is given that the above system of equations has infinitely many solutions. So,

$\dfrac{a}{3}=\dfrac{b}{4}=\dfrac{10}{20}$

$\dfrac{a}{3}=\dfrac{b}{4}=\dfrac{1}{2}$

Now,

$\dfrac{a}{3}=\dfrac{1}{2}$ and $\dfrac{b}{4}=\dfrac{1}{2}$

$a=\dfrac{3}{2}$ and $b=\dfrac{4}{2}$

$a=1.5$ and $b=2$

So, a=1.5 and b=2.

Now,

$\dfrac{a}{b}=\dfrac{1.5}{2}=0.75$

Therefore, $\dfrac{a}{b}=0.75$ .

5 0

4 years ago

What is the value of x in the triangle?

topjm [15]

Answer:

Step-by-step explanation:

Using the sine ratio in the right triangle and the exact value

sin30° = $\frac{1}{2}$ , then

sin30° = $\frac{opposite}{hypotenuse}$ = $\frac{x}{8}$ = $\frac{1}{2}$ ( cross- multiply )

2x = 8 ( divide both sides by 2 )

x = 4

7 0

3 years ago