3x + 11.63 = 20
3x + 11.63 - 11.63 = 20 - 11.63
3x = 8.37
by subtracting the 11.63 from both sides, this tells us how much the grapes cost....not per lb., but for the total of all the grapes.
        
             
        
        
        
Parallel:  the lines have = slopes.  We thus need 5/6 to equal 2/p.  then 5p must equal 12, and p = 12/5.   (answer)
Check:  Is 5/6 = 2 / (12/5)?  YES
Perp.:  The lines have slopes that are negative reciprocals of one another.
Then -6/5 = 2/p,  or
 -6      2
---- = ----
  5      p             Thus, -6p = 10, and p = -5/3   (answer)
        
                    
             
        
        
        
Step-by-step answer:
This is a regular heptagon, means it has 7 <em>congruent</em> sides and 7 <em>congruent </em>vertex angles.
To work with polygons, there is a very important piece of information that you must know to solve the majority of related problems.
This is:
sum of exterior angles of polygons = 360 degrees.
If you don't remember the 360 degrees, think of the sum of exterior angles of an equilateral triangle, which is 3*(180-60)=3*120=360!  It works!
For a regular heptagon, c = 360/7=51.43 degrees approx.
This means that each vertex angle measures 
vertex angle = 180-c
So since 2d+the vertex angle = 360, we have
2d+(180-c)=360
solve for d:
2d=360-(180-c)=180+c 
d=(180+c)/2=90+c/2=115.71 degrees. (approx.)
 
        
             
        
        
        
Answer:
Three solutions.
Step-by-step explanation:
In order to solve system of equations by graphical method, we graph the system of equations. The intersection point (s) of the two graph would give us the solution. 
If the graph of the equations intersect at 2 points then there will be 2 solutions, if there are 4 intersection then there would be 4 solutions and so on.
For the given graph, we  can see that there are three intersection points. 
Hence, there would be three solutions.