1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
eimsori [14]
2 years ago
12

Someone please explain this step by step:

Mathematics
1 answer:
Volgvan2 years ago
3 0

Answer:

  13

Step-by-step explanation:

Perhaps the most straightforward way to find the value of the given function is to first solve the equations for x and y. The results can be substituted into your expression to find the value you want.

__

<h3>solving the system</h3>

We notice the y-coefficients are opposites, so we can eliminate the y-variable by adding the equations.

  (2x -y) +(x +y) = (3) +(1)

  3x = 4 . . . . . . simplify

  x = 4/3 . . . . . divide by 3

The value of y can be found from the second equation:

  4/3 +y = 1 . . . . substitute for x

  y = -1/3 . . . . . . subtract 4/3

<h3>expression value</h3>

The value of 8x-7y is found by substituting the x- and y-values into this expression:

  8(4/3) -7(-1/3) = 32/3 +7/3 = 39/3 = 13

The value of 8x-7y is 13.

_____

<em>Additional comment</em>

You can also work out what combination of the two equations will give 8x -7y. That turns out to be 5 times the first minus 2 times the second:

  5(2x -y) -2(x +y) = 5(3) -2(1)

  10x -5y -2x -2y = 15 -2

  8x -7y = 13

__

The coefficients 5 and -2 are found by solving the system of equations ...

  a(2x -y) +b(x +y) ≡ 8x -7y   ⇒   {2a +b = 8, -a +b = -7}

You might be interested in
Which equation represents an exponential function with the initial value of 500?
EastWind [94]

Answer:

A exponential equation is usually of the form f(x)=a (1±r)ˣ.

Our limitation: Initial Vale is 500.

Let's look at our options:

#1- Initial Value of 1000  --- WRONG!

#2- Initial Value of 1000  --- WRONG!

#3- Initial Value of 500 ---- Maybe

#4- Initial Value of 500 ---- Maybe

Let's look at 3 and 4:

#3- Fits Our Form of f(x)=a (1±r)ˣ ---- CORRECT!

#4- Does not fit Our Form of f(x)=a (1±r)ˣ, It's to the 2nd power, not the x power! ---- WRONG!

Hence, #3 Is correct!

Step-by-step explanation:

Well, I hope you understood, and I'd gladly explain anything that didn't make sense. A brainliest would be appreciated, thank you!

-Zylynn Jade Ardenne

5 0
2 years ago
Carla wants to create a garden in her backyard. She wants the width of the garden to be 9 meters and the area to be 162 meters.
Naddik [55]
<h3>Answer:  18</h3>

Work Shown:

area = length*width

length = area/width

length = 162/9

length = 18 meters

7 0
2 years ago
Eric and Sue will randomly select from a treat bag containing 3 lollipops and 2 gum balls. Eric will select, replace it, and the
Vilka [71]

Answer:

Sue has the greater probability of 2/5 and Eric has the probability of 1/5.

Step-by-step explanation:

Sue took 2 things and eric replaced his forst one, ending up with one treat.

8 0
3 years ago
The graph of y= f(X) is shown below, what point could be used to find f(3)?
balandron [24]

Answer:

Point A

Step-by-step explanation:

The long that would be used to find f(3) is the point that shows the value of y when x = 3.

Looking at the graph given, the only point that shows the value of y when x = 3 is point A.

When x = 3, y = 0.

Therefore, f(3) = 0.

8 0
3 years ago
If a fish swims 7/8 of the depth of 32 foot deep lake, how many feet down did the fish swim?
erastova [34]
The answer is 8÷32 4 4×7 28
4 0
3 years ago
Other questions:
  • Write 7,000+600+10+2 in standard form
    6·2 answers
  • The letters c, a, t are placed in a bag. Each letter is randomly drawn from the bag and not replaced. Complete the table to show
    6·1 answer
  • The new pencil is 19 centimeters long how many millimeters long with a pencil
    7·1 answer
  • A rectangular container is 12cm long, 11cm wide and 10cm high. The container is filled with water to a depth of 8cm. A metal sph
    5·1 answer
  • The area of a square gate is 361 feet squared what is the length of any side of the gate
    12·1 answer
  • Find the constant of variation k for the direct variation.<br><br> 2x + 6y = 0
    12·1 answer
  • Simplify 3 x n x p x 6
    13·1 answer
  • Some biologists believe the evolution of handedness is linked to complex behaviors such as tool-use. Under this theory, handedne
    6·1 answer
  • Algebra help please!!!!!!!
    6·2 answers
  • Can someone help me on my question pls
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!