00:01
So for chapter 5, section 2, question 38, we have x plus y plus z.
00:16
I'm just going to call them that is going to equal $120 ,000 in investments.
00:28
You also have the interest rates of 022x plus 0 .06 y minus 0 .02c.
00:46
2 ,820 and you know that y is going to equal 10 ,000 plus c also moves in to the opposite side is why my c equals 10 ,000 so the first thing i want to do here is multiply row 1 by 0 .22 and subtract that from line 2 in order to remove my x from line 2 to satisfy equation 3 so x plus y plus c is going to equal $120 ,000.
01:41
Now, this next line changes to negative 0 .38y plus 0 .042z equal to negative 180.
01:59
And line 3 saves the same.
02:02
Y minus z equals 10 ,000.
02:09
Now we can multiply line 2 or line 3 by 0 .038, add that to, hold on, i'm just putting row, but this is a line into row.
02:31
To be consistent, i'll use that line.
02:33
I'll use that line, and i'm going to add them together in order to get rid of my y value, and therefore i'll be able to solve for z...