More math fun !?

Question

1. Points A(3,5) and B(-1,-3) lie on the line y=2x-1. Determine which of the following points is collinear to A and B.
a. 4,6 b.-3,-1 c.1,1 d. 3,-3

2. Determine the value of r so that a line thorugh (r,3) and (7,4) has a slope of 1/2.

3. THe faces of a cube are numbered with consecutive numbers. Three of the numbers are shown. WHat are the possible sums of the numbers on all the faces of the cubes? (23, 20, 19)

4. Write a conjecture : Given: M is the midpoint of line AB

5. How many lines can be drawn containing three collinear points?

Answer 1

1. Points A(3,5) and B(-1,-3) lie on the line y=2x-1.
Determine which of the following points is collinear to A and B.
a. 4,6 b.-3,-1 c.1,1 d. 3,-3

c. (1,1) is collinear since it also lies on the line y=2x-1

2. Determine the value of r so that a line thorugh (r,3) and (7,4) has a slope of 1/2.

slope = 1/2
(y2 - y1) / (x2 - x1) = 1/2
(4 - 3)/(7 - r) = 1/2
1/(7 - r) = 1/2
7 - r = 2
r = 5