Expert: Scott A Wilson - 9/19/2011

Question
The domain of x is {-1, 0, 2}.  Solve the equation:

-2x + y = -3

Correct
2. The domain of x is {-1, 0, 2}.  Solve the equation:  

6x - 0.5y = 3

Correct
3. Complete the ordered pairs to solve:  

4x + 3y = 8;  (0,___);  (___ ,0);  (5,___)

Correct
4. Complete the ordered pairs to solve:

 3x + 5y = 3;  (1,____);  (-0.67,____);  (____ ,1.4)

Correct
5. Complete the ordered pair to solve: -x + 4y = 9; (-1, ___ )
Incorrect
6. Complete the ordered pair to solve: 5x + 6y = 17; (1, ___ )
Incorrect
7. Complete the ordered pair to solve: x - 3y = 7; ( ___ , -2)
Correct
8. Complete the ordered pair to solve: 2x + y = 5; (4, ___ )
Incorrect
9. Complete the ordered pair to solve: 5x + 2y = -8; ( ___ , 1)
Incorrect
10. Find the value of k so that the ordered pair satisfies the equation:  

3x - y = k;  (1,3)

Incorrect
11. Find the value of k so that the ordered pair satisfies the equation:

6x - ky = k;  (2,2)

Correct
12. Solve the equation if the variables represent whole numbers:  

2x + y = 6

Correct
13. Solve the equation if the variables represent whole numbers:  

5x + 2y = 30

Correct
14. Solve the equation if the variables represent whole numbers:

2x + y = 6

Incorrect
15. Find the value of k so that point P lies on line L:

P:  (2,3);  L:  kx - 2y + k = 0

Incorrect
16. Find the value of k so that point P lies on line L:

P:  (k,-2);  L:  3x + 2y = k

Incorrect
17. Find the coordinates of the point where the graph intersects for:  

x - 2y = -4 and 3x + 2y = 12

Incorrect
18. Find the slope of the line containing:  

(4,3) and (0,1)

Incorrect
19. Find the slope of the line containing:

(3,-1) and (-3,1)

Incorrect
20. Find the slope of the line containing:  

(.5,-2) and (0,-4)

Correct
21. Find the slope of the line:

4y - 5 = 6x

Incorrect
22. Find the slope of the line:  

2(1 - y) = x

Correct
23. Find the slope of the line:

0.25x - 0.5y = 1

Incorrect
24. Find the slope of the line:          
1 x -
-1 y
= 1
  
3 5

Correct
25. Find the value of k so that the line has slope m:  

6x + ky = 10 and m = -2

Incorrect
26. Find the value of k so that the line has slope m:          
(k + 1)x + 2y = 6 and m = -
1
3

Incorrect
27. Describe the line containing the points:  

(-4,-6) and (11,-6)

Correct
28. Describe the line containing the points:  

(3,7) and (3,0)

Incorrect
29. Find the slope:  

(9,2) and (5,8)

Correct
30. Find the slope:  

(-8,-2) and (-4,8)

Correct
Part 2
Type the answer to the problem in the text box below each item. Be sure legibly show all work in your notebook. Remember to include any applicable units. If there is no solution, type "no solution". If there is not enough information present to solve the problem, type "not enough information". (Each question is worth one point)
31. Find the slope:

(-3.5,-7) and (-1.5,-7)

Correct
32. Find the slope:

x + y = 7

Incorrect
33. Find the slope:

x - y + 1 = 0


34. Find the slope:

2x + 4y = 5

Incorrect
35. Find the slope:

4x - 3y = 3

Answer
I assume if they are labeled correct, you got them right?
I will look at problems marked incorrect.


5. Complete the ordered pair to solve: -x + 4y = 9; (-1, ___ )
If x is -1, -x is 1, so we have 1 + 4y = 9 => 4y = 8 => y = 2.

6. Complete the ordered pair to solve: 5x + 6y = 17; (1, ___ )
x=1, 5x=5, so 5+6y=17, so (-5 from both sides) 6y=12, so (divide both sides by 6) y=2.

8. Complete the ordered pair to solve: 2x + y = 5; (4, ___ )
If x=4, then 2x=8, so 8+y=5, do add -8 to both sides, giving y = -3.

9. Complete the ordered pair to solve: 5x + 2y = -8; ( ___ , 1)
If y=1, then 2y=2, so 5x+2=-8, so -2 to both sides gives 5x = -10,
and division by 5 gives x = -2.

1. Find the value of k so that the ordered pair satisfies the equation:  
3x - y = k;  (1,3)
Put in 1,3 for x,y and get 3(1) - 3 = 3 - 3 = 0, and that's k.

14. Solve the equation if the variables represent whole numbers:
2x + y = 6
If x=0, y=6
If x=3, y=0
If x=6, y=-6
If x=6n (where n is some integer), y=6-2n.

15. Find the value of k so that point P lies on line L:
P:  (2,3);  L:  kx - 2y + k = 0
Solve 2k - 2*3 + k = 0.
This is the same as 2k - 6 + k = 0.
Combining the k's and adding 6 to both sides gives 2k = 6, so k=2.

16. Find the value of k so that point P lies on line L:
P:  (k,-2);  L:  3x + 2y = k
Input k for x, -2 for y, and solve for k.

17. Find the coordinates of the point where the graph intersects for:  
x - 2y = -4 and 3x + 2y = 12
Add the equations, getting 4x = 8, so x=2; put back in either equation and solve for y.

18. Find the slope of the line containing:  (4,3) and (0,1)
Compute (3-1)/(4-0)

19. Find the slope of the line containing: (3,-1) and (-3,1)
Find (1 - -1)/(-3 - 3)

21. Find the slope of the line: 4y - 5 = 6x
Put in the form y = mx + b.
That is, 4y = 6x + 5, so y = 1.5x + 1.25, so the slope is m, or 1.5.

23. Find the slope of the line: 0.25x - 0.5y = 1
Put in the form y = mx + b by adding -0.25x to both sides,
then dividing both sides by -0.25.

25. Find the value of k so that the line has slope m:  6x + ky = 10 and m = -2
That is ky = -6x + 10, so y = -6x/k + 10/k, so -6/k = m, and m = -2, so -6/k = -2, so k = =3.

26. Find the value of k so that the line has slope m:          
(k + 1)x + 2y = 6 and m = -
1
3

Multiply out and put in the form y = mx + b so for m an expression for k is gottem.
Put in m and solve for k.

28. Describe the line containing the points:  (3,7) and (3,0)
Slope is m=(y2-y1)/(x2-x1), equation is then y-y0 = m(x-x0).

Part 2
Type the answer to the problem in the text box below each item. Be sure legibly show all work in your notebook. Remember to include any applicable units. If there is no solution, type "no solution". If there is not enough information present to solve the problem, type "not enough information". (Each question is worth one point)

32. Find the slope: x + y = 7
Subtract x from both sides, giving y = -x + 7, so slope is -1.

33. Find the slope: x - y + 1 = 0
This is y = x + 1, so slope is 1.

34. Find the slope: 2x + 4y = 5
Subtract 2x from both sides, giving 4y = -2x = 5.
Divide both sides by 4, giving y = -0.5x + 1.25, so slope is -0.5.

35. Find the slope: 4x - 3y = 3
Subtract 4x from both sides, giving -3y = -4x + 3.
Divide entire equation by -3, giving y = -4x/3 - 1.
The slope is then -4/3.