00:01
In this problem, we have three different models of desks, model x, model y, and model z, and we have three steps in the desk making process.
00:11
So we have cutting, construction, and finishing.
00:14
And for each model, the steps take a different amount of time.
00:18
But we're given three total available amounts of time.
00:24
So we have 100 hours available for cutting, 100 for construction, and then 65 hours for finishing.
00:30
And so we want to figure out which type of desk should be produced each week if we have this amount of time each week for each step.
00:39
And so from this information, we can write a system of three equations to figure out how many of x, y, and z should be produced.
00:48
So our first equation is going to be the cutting equation.
00:51
So we have two hours for x for cutting x.
00:56
So if we take 2 times x, we will get the total amount of time that we need to cut the models of the x desk.
01:07
And then we can do the same thing for y, so 3 times y plus 2 times z.
01:13
And then the total amount of cutting we have is 100 hours.
01:18
So for our second equation, we can do the same thing with construction.
01:21
We have 2x again, and then y.
01:25
So 1 times y is just y and then 3 times z is equal to 100 and then same thing for the finishing we have just x plus y plus 2 z is equal to 65 so now we have a system of three equations that we can solve using elimination and our first step is going to be to subtract our second equation from our first equation so we can eliminate the 2 x variables so if we have have 2x minus 2x, the x is eliminated.
02:00
If we have 3y minus y, that gives us 2y, and then 2z minus 3z gives us minus z, and then 100 minus 100 is just 0.
02:11
And now we can take our third equation and multiply it by 2...