00:01
For this problem, we are going to solve the systems of equations using a graph and a symbolic method.
00:09
I'm going to start with graphing.
00:11
To graph the equations, i must first solve them for y.
00:15
So x minus 4y equals 15.
00:20
I'm going to subtract x on both sides.
00:23
Negative 4y equals negative x plus 15.
00:28
And then i'm going to divide by negative 4.
00:35
Y equals 1 4th x minus 15 fourths.
00:43
Now i've got kind of a think bubble over here.
00:45
I know that negative 15 fourths is almost 4.
00:51
So it's going to be negative 3 .75.
00:55
But i want to keep everything in fraction form because it's easier to graph.
00:59
So if we have negative 3 .75, that is going to be about here for our y intercept.
01:10
And then my slope says to go up one and over four with the one -fourth.
01:18
Maybe we'll go backwards some two, down one and backwards four.
01:25
Maybe one more, down one and backwards four.
01:28
So here's, this is kind of estimating.
01:35
So it's not going to be perfect with graphing.
01:41
On our second equation, it is 3x minus 2y equals 15, and i'm going to subtract 3x.
01:52
Negative 2y equals negative 3x plus 15, and then we divide by negative 2.
02:03
Y equals 3 halves x minus 15 halves.
02:11
That 15 halves is about 7 .5 or is 7 .5.
02:16
So this is negative 7 .5.
02:19
So this is going to be down 4, 5, 6, 7 and a half is down here.
02:27
And then we're going to go up 3...