00:01
So for this question, we're going to be graphing some equations.
00:03
So we have equations that kind of represent the number of men receiving degrees and the number of women receiving degrees during a time period.
00:11
So the equation for the number of women receiving degrees is y equals 3 .9x plus 443.
00:27
Sorry, this is actually for men, not for women.
00:30
And then for women, it's y equals 14 .2x plus 314.
00:38
This is for women.
00:39
We also have an image down here of the graphs.
00:42
We're going to get to that in part c.
00:43
So just ignore that for now.
00:45
So the first thing is we want to use substitution to solve for the systems of equation.
00:49
So what we're going to do is set these two equal to each other.
00:52
And the reason that we can do that is because they're both equal to y.
00:54
So we can substitute them in for y.
00:57
So we're left with 3 .9x plus 443 equals 14 .2x plus 314.
01:07
So we're going to subtract 3 .9x from both sides.
01:10
And now we're left with 443 equals 10 .3x plus 314.
01:18
Then we're going to subtract 314 from both sides.
01:20
And we're going to be left with 129 equals 10x.
01:25
And if you divide both sides, sorry not 10x, 10 .3x.
01:31
10 .3x.
01:33
If you divide both sides by 10 .3, you'll get that x equals about 12 .53.
01:40
Okay? so since x represents the number of years after 1970, let's round this 12 .53 to 13.
01:47
Because we're not really looking at 12 .53 years.
01:49
We kind of want to look at like whole years...