00:01
All right, we're checking for solutions on number five.
00:05
We want to see if part a is a solution to the system of linear equations and also part b.
00:10
So for part a, i'm going to take the point negative 3, negative 3, which means both my x and my y value are negative 3.
00:17
And i'm going to see if that point falls on both of my lines.
00:21
Now, the way i do that is by plugging in my values for x and y and seeing if the statement is true.
00:26
So the equation is just a sentence, and we want to see if that sentence is a true statement.
00:32
So my first equation is 2y equals 4x plus 6.
00:36
So where i see y and x, i'm going to replace it with their values of negative 3.
00:45
So starting on the left hand side, i have 2 times negative 3.
00:48
So negative 6 is on the left hand side of my equation.
00:53
So now i have to see if the right hand side is also going to be negative 6.
00:56
So 4 times negative 3 is negative 12 plus 6, which is in fact negative 6.
01:05
So since it works, we have to check the second equation.
01:09
So negative 6 is equal to negative 6.
01:11
Since that's true, that means i need to check the second equation for that point.
01:16
So 2x minus y equals negative 3 is my second equation.
01:20
Once again, i'm plugging in negative 3 for both my x and my y values.
01:29
And seeing if this is a true statement.
01:32
So 2 times negative 3 is negative 6.
01:34
I have a minus negative 3, which is the same as having plus 3.
01:38
So then negative 6 plus 3 is negative 3, which is equal to negative 3.
01:44
So that statement is true.
01:46
So therefore, since both of them are correct, that means that negative 3, negative 3 is a solution.
02:01
All right.
02:02
So checking for part b, part b, the point is 03.
02:07
So my x values are going to become zeros, and my y values are going to become 3.
02:15
So let's check our first equation, 2y equals 4x, plus...