Can you check these for me.
Directions: Find the slope of the line that passes through each pair of points.
1. (3,-8) and (-5,2)
Answer: -10/8
2. (-10,-3) and (7,2)
Answer: -5,-17
3. (-7,-6) and (3,-6)
Answer: 9
4. (8,2) and (8,-1)
Answer: 0 undefined
Directions: State whether the graphs of the following equations are parallel, perpendicular, or neither.
5. 2x+3y=4
3x+2y=6
Answer: parallel
6. 1/2x+2y=1
4x-y=3
Answer: parallel
7. 6x-9y=4
2/3x-y=11
Answer: perpendicular
8. y-7=0
3x=5
Answer: neither
Math Problem: A pyramid of aluminum cans is built against a wall so that there are two cans in the top row, four cans in the second row, six cans in the third row , and so on. How many rows are there if the pyramid contains 1190 cans?
Answer: 595 rows
Question 1-5:
slope is tangens of angle betwen x-axis and line.
Equation is:
tan(alpha)=(y2-y1)/(x2-x1)
Firs 5 question is O.K
Sorry. Answer for question 5 is not correct.
2x+3y=4 , 3y=-2x+4 (Divided with 3)
y=(-2/3)x+4/3 Slope (-2/3)
3x+2y=6 , 2y=-3x+6 (Divided with 2)
y=(-3/2)x+3 Slope(-3/2)
Question 6
(1/2)x+2y=1 , 2y=(-1/2)x+1
(Divided with 2) y=(-1/4)x+1/2
Slope(-1/4)
4x-y=3 , y=4x-3 (Slope 4)
Perpendicular
Question 7
6x-9y=4 , -9y=-6x*4 (Divided with -9)
y=(-6/-9)x-4/9
y=(2/3)x-4/9 Slope (2/3)
(2/3)x-y=11 , y=(2/3)x-11 Slope (2/3)
Parallel
Best way to check that is that you drive this lines in grid.Is enough 2 points for any lines.
For question 5 draw lines
(-2/3)x+4/3 and y=(-3/2)x+3
For question 6 draw lines
(-1/4)x+1/2 and y=4x-3
For question 7 draw lines
(2/3)x-4/9 and (2/3)x-11
Question 8
y-7=0 y=7
For all values of x y=7
That is line parallel with x-axis
3x=5 (divided with 3)
x=5/3
For all values of y x=5/3
That is line p0arallel with y-axis