I seriously don't understand this problem. The teacher didn't even teach us this and my notes in Algebra aren't helping either. I need an explanation to how it is solved, not just the answer...
2007-12-20 17:22:05 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
In order to find the slope (m) you must divide the change in y by the change in x.
(3a-a)/(8-4)=
(2a)/4=
a/2
We now know the slope is 2/a. We also know that the slope is 1/3. Next, we set them equal to each other and solve for a.
a/2=1/3
a=2/3.
Now that we know what "a" is, we can determine the original points.
(4,2/3) and (8,2)
2007-12-20 17:28:19 · answer #1 · answered by Anonymous · 2⤊ 0⤋
Given:
(4, a) & (8, 3a)
m = 1/3
Req'd:
a
Solution:
We know that the points above are expected to have a straight line, but we don't know a because it's a variable. So the points:
(4, a) are values of x & y respectively if you have the lecture about the rectangular cartesian coordinates. Same is true with (8, 3a).
Slope is the ratio of the change in y-axis and the change in x-axis. (Also the rise over run)
m = Îy/Îx, substituting the points in this equation:
1/3 = (3a - a)/(8 - 4)
1/3 = 2a/4
1/3 = a/2
a = 2/3
Substitute a back into the given points gives:
(4, 2/3) & [8, 3(2/3)]
(4, 2/3) & (8, 2)
2007-12-20 17:40:10 · answer #2 · answered by selang er uu 2 · 0⤊ 0⤋
simple...
(3a-a)/(8-4) is the slope of the line..obviously..
which gives a=2*3=6
2007-12-20 17:32:52 · answer #3 · answered by Anonymous · 0⤊ 1⤋
m = (3a - a) / (8 - 4)
m = 2a / 4
1 / 3 = 2a / 4
1 / 3 = a / 2
a = 2 / 3
2007-12-20 19:03:43 · answer #4 · answered by Como 7 · 0⤊ 0⤋