solve using the graphing method: y=7x-8, y=x+4

Question

I got this graphed I just don't know how to show all the work. Please help & use step by step, thank you. 

Answer 1

Easiest way to graph a line is find the intercept points and connect, then extend.

 

  Y = 7X -8

 

  Y intercept is  ( 0, -8)

 

  X intercept  ( 8/7, 0) / give Y=0 and solve for X

 

  Y = X +4

 

     Y intercept = (0,4 )

     

       X  intercept ( -4,0)

 

 After graphing in Scale  You read the coordinate of the point where 2 lines intersect.

 

      Should be ( 2,6) ,  Solution of System of equation:

    

      Y= X +4

      Y =7X -8

        

      To solve:

        X +4 = 7x -8

 

        6X = 12      X =2

        Y = 2 +4     Y = 6

 

      Intersect point : ( 2,6)

   

      Graph and equations both equally show the relationship between 2 objects.

 

        

Answer 2

Hi again Deanna;

The easiest technique to find where the two points intersect is to subtract one equation from the other.

y=7x-8

-(y=x+4)

y-y=0

7x-x=6x

-8-4=-12

0=6x-12

Let's add 12 to both sides...

12=6x

Let's divide both sides by 6...

2=x

Let's plug x-value into the first equation...

y=7x-8

y=7(2)-8

y=14-8

y=6

Let's double-check with the other equation...

y=x+4

y=2+4

y=6

The two lines intersect at (2,6).

Answer 3

Well, the beauty of the graphing method is that there's not a lot of work to show.

 

Here, "solve" means "find the point where these two lines intersect.

 

Once you've graphed the two lines, find the x- and y-coordinates of the point where they meet, and you're done!