00:01
So i have three equations here.
00:01
Are there any equations that i can easily combine by just adding or subtracting them? well, i notice all my zs have similar coefficients.
00:10
So if i just add one and two together, that'll give me 4x plus 4y.
00:19
Zs cancel equals 12.
00:21
And then i can divide by 4 on both sides or divide by 4 to each term separately, which will give me x plus y equals 3.
00:29
I also noticed that i could add just equations 1 and 3 together.
00:35
And when i do that, i'm going to get 2x plus 2y, z's cancel, equals 6, and then i could divide by 2 to both sides to the equation, or divide by 2, to both, to every single term.
00:51
And now what i notice, x plus y equals 3 and x plus y equals 3, therefore if i subtracted those two equations, i would get 0 equals 0, which in terms, indicates i have dependent solutions.
01:03
So i have more than one answer.
01:06
So what i'm going to end up doing is i'm going to write everything in terms of z.
01:11
So when i finally finish the problem, the answer will be my x value in terms of z, my y value in terms of z.
01:21
And then i'm just going to write z in terms of z.
01:24
Okay.
01:24
So z is itself...