All categories

3 years ago

What is the y-coordinate for the solution of the system of equations below? 7y+5x=19 3y+5x=7

2 answers:

7 0

I would go about solving this by elimination because the x variables are already the same so all you would have to do is change one equation to the opposite signs and add them, so it would look like:

7y + 5x = 19
+ -3y - 5x = -7
-------------------
4y=12
y=3

IceJOKER [234]3 years ago

6 0

7y + 5x = 19 <u />⇒ 21y + 15x = 57
3y + 5x = 7   ⇒ <u>21y + 21x = 49</u>
   -<u>6x</u> = <u>8</u>
      -6   -6
   x = -1 1/3
       7y + 5x = 19
   7y + 5(-1 1/3) = 19
   7y - 6 2/3 = 19
   <u>    +6 2/3 +6 2/3</u>
      <u>7y</u> = <u>25 2/3</u>
   7 7
      y = 3 2/3
      (x, y) = (-1 1/3, 3 2/3)

You might be interested in

A figure has vertices at the points (6,5), (6,-4), (-4,-4) and (-4,5). What is the area of the figure

Oxana [17]

Answer:

90 units²

Step-by-step explanation:

The rectangular figure is 10 units wide (from -4 to +6) and 9 units high (from -4 to +5), so its area is 10·9 = 90 square units.

7 0

3 years ago

Need help pls<br>thank you in advance

ira [324]

Answer:

<u />

$\textsf{Mean}\:\overline{X}=\sf \dfrac{\textsf{sum of all the data values}}{\textsf{total number of data values}}$

$\implies \sf Mean\:(Nilo)=\dfrac{5+6+14+15}{4}=\dfrac{40}{4}=10$

$\implies \sf Mean\:(Lisa)=\dfrac{8+9+11+12}{4}=\dfrac{40}{4}=10$

<h3><u>Standard Deviation</u></h3>

$\displaystyle \textsf{Standard Deviation }s=\sqrt{\dfrac{\sum X^2-\dfrac{(\sum X)^2}{n}}{n-1}}$

$\begin{aligned}\displaystyle \textsf{Standard Deviation (Nilo)} & =\sqrt{\dfrac{(5^2+6^2+14^2+15^2)-\dfrac{(5+6+14+15)^2}{4}}{4-1}}\\\\& = \sqrt{\dfrac{482-\dfrac{40^2}{4}}{3}}\\\\& = \sqrt{\dfrac{82}{3}}\\\\& = 5.23\end{aligned}$

$\begin{aligned}\displaystyle \textsf{Standard Deviation (Lisa)} & =\sqrt{\dfrac{(8^2+9^2+11^2+12^2)-\dfrac{(8+9+11+12)^2}{4}}{4-1}}\\\\& = \sqrt{\dfrac{410-\dfrac{40^2}{4}}{3}}\\\\& = \sqrt{\dfrac{10}{3}}\\\\& = 1.83\end{aligned}$

<h3><u>Summary</u></h3>

Nilo has a mean score of 10 and a standard deviation of 5.23.

Lisa has a mean score of 10 and a standard deviation of 1.83.

The <u>mean</u> scores are the <u>same</u>.

Nilo's standard deviation is higher than Lisa's. Therefore, Nilo's test scores are more <u>spread out</u> that Lisa's, which means Lisa's test scores are more <u>consistent</u>.

5 0

2 years ago

Solve x42=37 x 42 = 3 7 using two different strategies. Explain each strategy.

Dafna11 [192]

Given equation : $\frac{x}{42}=\frac{3}{7}$ .

Strategy 1: We can cross mutiply both sides remove fraction form.

On cross multiplication, we get

x * 7 = 3 * 42

7x = 126.

Dividing both sides by 7, we get

Strategy 2: We can find least common denominator(lcd) of both sides and multiplying both sides by that lcd to get rid denominators from both sides.

LCD of 42 and 7 is 42.

Therefore, multiplying both sides by 42, we get

$42\times \frac{x}{42}=42\times\frac{3}{7}$

x = 6 * 3

4 0

3 years ago

what geometric shape may describe a quadrilateral that has two sides with length 8 cm and two sides with length 5 cm

777dan777 [17]

Perimeter<span> and area are two important and fundamental mathematical questions</span>

6 0

3 years ago

Read 2 more answers

. Tickets to a football game cost a dollars for adults and s dollars for students. If a family of 2 adults and 3 students buy ti

garri49 [273]

Answer:

Choice C is the answer.

Known information:

a = adult $

s = student $

We have 2 adults and 3 students.

Step-by-step explanation:

To find the total price of tickets given a # of students and adults, multiply a by the # of adults and multiply s by the # of students. Therefore, it would look like this:

2a + 3s = price

Therefore, choice C is the answer.

Hope this helps!

3 0

2 years ago