00:01
And this problem, we're being asked to solve a system of equations using our graphing calculator.
00:08
So the first thing we have to do is get our equation, x squared plus y squared equals 68, and solve for y.
00:16
So the top side of our circle, which is the positive and the bottom, which is the negative.
00:23
And we have the square root of 68 minus x squared.
00:29
Now getting our second equation, we've got y squared minus 3x squared equals 4.
00:38
And that tells us we're going to have a vertical hyperbola.
00:43
And so we're going to have the top side of the hyperbola, which is the plus, the bottom side of the hyperbola, which is the minus, and the square root of 4, 4 plus 3x squared.
01:02
Now we're ready to get our graphing calculator.
01:05
So we'll go get our graphing calculator here.
01:10
And we're going to plug in our equations.
01:12
So we're going to go to y equals and helps you out.
01:15
This will show you the buttons i'm pressing down here at the bottom.
01:22
So doing our first one, we're going to need a square root.
01:25
So there's our square root of 68 minus x squared.
01:37
And then we're going to go down to the next one.
01:38
We'll do the minus or the negative square root.
01:42
So we want to use this negative sign down here at the bottom.
01:44
We do not want to use the minus sign.
01:48
And we have the square root, again, of 68 minus x squared.
01:57
For our second set, again, i'm going to do the positive first.
02:01
It doesn't matter which one you do.
02:02
But i'm going to do the positive first.
02:05
And there's our 4 plus 3x squared.
02:10
And then i'm going to come down here and again, catch the negative, and do my negative principal square root of 4 plus 3x squared.
02:23
Now we need to get a graph of this, so i'm going to press zoom 6 and see how it looks.
02:30
There's my circle.
02:32
My scale's not exactly.
02:34
So it looks kind of more like an ellipse.
02:38
There you go.
02:39
Now we want to find these four intersection points because those are our solutions.
02:43
So to find those, i'm going to do second trace.
02:47
And when we bring up this calculate menu, we see that the fifth one is intersect.
02:51
So i'm going to press 5 and it picks a curve...