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
BlackZzzverrR [31]
3 years ago
14

–7x + 8y = 1

Mathematics
2 answers:
Mademuasel [1]3 years ago
8 0

Answer: -6

Step-by-step explanation:

First, try deleting the x-coordinate from the equations by making them the same number. By doing that I multiplied the first equation (-7x+8y=1) by 4 and (4x-8y=20) by 7. That got me -28x+32y=4 and +28x-56y=140. You could cross out the 28 which gets +32y=4 and -56y=140. Then add up both equations. It’s gets you -24y=144

-24y=144

—————— then divide by -24

-24 -24

144/-24=-6

Hope this helped!

Step2247 [10]3 years ago
4 0

\bf \begin{cases} -7x+8y=1\\ 4x-8y=20 \end{cases}\qquad \qquad \stackrel{\textit{using elimination}}{ \begin{array}{llll} -7x~~\begin{matrix} +8y \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~=1\\ ~~4x~~\begin{matrix} -8y \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~=20\\ \cline{1-1}\\ -3x~\hfill =21 \end{array}}

\bf x=\cfrac{21}{-3}\implies \blacktriangleright x=-7 \blacktriangleleft \\\\\\ \stackrel{\textit{substituting in the 2nd equation}}{4(-7)-8y=20}\implies -28-8y=20\implies -8y=48 \\\\\\ y=\cfrac{48}{-8}\implies \blacktriangleright y = -6 \blacktriangleleft

You might be interested in
16x^0+2x^2*y^-1 x=2 y=4<br> PLEASE HELP!!!
Kipish [7]

Answer:

your answer should be 4095

3 0
3 years ago
Consider this composite figure made of a cone and a cylinder. A cone has a height of 8 centimeters and radius of 3 centimeters.
dangina [55]

The volume of cone is 75.4 cubic centimeters and the volume of cylinder is 197.92 cubic centimeters. The volume of composite figure is 273.32 cubic centimeters.

Step-by-step explanation:

The given is,

                Composite figure made of a cone and a cylinder.

                A cone has a height of 8 centimeters and radius of 3 centimeters.

                A cylinder has a height of 7 centimeters and radius of 3 centimeters.

Step:1

              Volume of composite figure = Volume of Cone +

                                                                 Volume of cylinder............(1)

Step:2

            Formula for volume of cone,

                   Volume of cone, V_{cone} = \pi r^{2} \frac{h}{3}....................(2)

           Where, r - Radius of cone

                       h - Height of cone

           From the given,

                            r = 3 centimeters

                           h = 8 centimeters

           Equation (2) becomes,

                                                   = \pi (3^{2} )(\frac{8}{3})

                                                   =\pi (9)(2.667)

                                                   = (3.14 × 9 × 2.667)           (∵ \pi = 3.1415)

                                                   = 75.4

                Volume of cone, V_{cone} = 75.4 cubic centimeters

Step:3

           Formula for volume of cylinder,

                   Volume of cone, V_{cone} = \pi r^{2} h....................(2)

           Where, r - Radius of cylinder

                       h - Height of cylinder

           From the given,

                            r = 3 centimeters

                           h = 7 centimeters

           Equation (2) becomes,

                                                   = \pi (3^{2} )(7)

                                                   =\pi (9)(7)

                                                   = (3.14 × 9 × 7)           (∵ \pi = 3.1415)

                                                   = 197.92

                Volume of cylinder, V_{cylinder} = 197.92 cubic centimeters

Step:4

         Equation (1) becomes,

            Volume of composite figure = 75.4 + 197.92

                                                            = 273.32 cubic centimeters    

Result:

           The volume of cone is 75.4 cubic centimeters and the volume of cylinder is 197.92 cubic centimeters. The volume of composite figure is 273.32 cubic centimeters.                    

3 0
3 years ago
Heyyyy have a good day!<br><br><br><br><br><br><br><br><br><br> :)
inn [45]

Answer:

I've learned that I can always learn more.

Step-by-step explanation:

7 0
2 years ago
Anais bought
galben [10]

Answer: She used  72 inches

Step-by-step explanation:

2 1/2 yds = 90 inches bought

12+6=18 left over

90-18=72

4 0
3 years ago
Based on the graph shown, what is the rate of change?
Margaret [11]

Answer:

A) 60 miles/hour

Step-by-step explanation:

7 0
3 years ago
Other questions:
  • When would you use herons formula in the real world?
    9·2 answers
  • Help now now now!!!!!!!!!!!!!!
    6·2 answers
  • An average score of 90 or above in an English course receives an A grade. A student has grades of 81, 87, 94, 93 on four tests.
    13·1 answer
  • 2(x-3)+5=3(x-1) how to solve?<br>​
    7·1 answer
  • a shower head use is about 6 gallons of water per minute given m, the number of minutes write an equation that can be used to fi
    12·1 answer
  • Find all numbers that are not in the domain of the function
    13·1 answer
  • The slope of a line passing through (-3,-6) and (-6,-6)
    15·1 answer
  • Does the table represent a function? Why or why not? X 2 3 3 4 5 y 4 5 6 7 7​
    6·1 answer
  • Which is the correct graph and solution for the following system of equations y=2x+3 y=-x-6
    7·2 answers
  • Can someone please help me <br><br> Solve for y. Show your work<br> 1. y - 3x &lt; 5
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!