00:01
Number eight, we're just testing points to see if they are solution to a system of linear equations.
00:07
And i'm going to plug in my variables and see if it gives me true statements for both equations.
00:12
Now, the first point for part a is pretty simple, but part b is a little more complicated because it has fractions.
00:18
So we're going to work through that.
00:20
So for the first one, i'm going to go ahead and plug in zero for my x value and one for my y value.
00:26
I'm going to start with the first equation.
00:27
So 4 times 0 equals 1 minus 1.
00:35
So 4 times 0 is 0.
00:37
1 minus 1 is 0.
00:39
So therefore it is good for the first equation.
00:42
So i'm going to check my second equation.
00:47
So x is 0 again.
00:49
So 0 minus 3 times 1 is that equal to negative 8.
00:55
Negative 3 times 1 is negative 3, which is not equal to negative 8.
01:00
So therefore, the first point, 01, is not a solution to the system of linear equations, which means it's not the intersection point to those two lines.
01:20
All right, part b, a lot more difficult because it's fractions.
01:25
It takes a little bit of work.
01:29
My x value is one -sixth.
01:31
My y value is one -third.
01:33
Now, if you have a nice calculator, you can just put in the equation and see if it's true.
01:40
But i'm going to do the algebra so that we can see how that works.
01:45
So for the first equation, i have 4x equals 1 minus y.
01:49
So i'm going to have 4 times 1 6th.
01:53
And i'm going to put 4 over 1 so that i can multiply that out equals 1 minus 1 3rd.
02:05
All right.
02:06
So i'm going to simplify before i even multiply these fractions on the left.
02:12
So both 4 and 6 are even.
02:14
So i can divide them by two and this becomes a two and this becomes a three...