00:02
For the first part of this problem, we want to write a linear equation representing the situation where the manager is buying x shares of ford motor company stock and y shares of general motors stock.
00:16
And so they're spending $15 .50 for each share of ford motorstock.
00:21
So that would be $1550 times the number of shares times x.
00:25
And then they're spending $62 .50 per share of general motor stock.
00:31
So that would be 6250 times y the number of shares.
00:36
And that should add up to the total amount of money spent, which was $484 ,375.
00:43
So that's the model to start us off.
00:46
Now for part b, we want to know how many shares of gm were purchased if 10 ,000 shares of ford were purchased.
00:54
So if x equals 10 ,000, then what is y? so we can compute that by substituting 10 ,000 in for x in our equation.
01:09
15 .5 times 10 ,000 plus 62 .5 times y equals 484 ,375.
01:23
So we can go ahead and work that out.
01:26
Okay, so when we multiply 15 .5 by 10 ,000, we get 155 ,000.
01:36
Then we want to subtract that from both sides of the equation.
01:41
When we do that, we have 62 .5y equals 329 ,375...