00:01
The good approach to this problem is knowing the equation of a circle that's centered at the origin with a radius of 7, r equals 7.
00:11
I should probably use a different color.
00:14
It looks like this.
00:15
It's x squared plus y squared equals the radius squared, so 7 squared.
00:22
And also what we know is we have the equation y equals 4x.
00:27
It's written a couple different ways, so i hope i have the right thing here.
00:33
But what i would do is substitute this y with 4x.
00:38
So what i'm looking at is x squared plus 4x squared is equal to 49.
00:47
And 4 squared is 16.
00:50
So when you add 1 to it, we're looking at 17x squared is equal to 49.
00:57
So if you divide that 17 over and then you square root both sides, the two x values are going to be, excuse me, positive 7 over root 17, as well as negative 7 over root 17.
01:16
And you could rationalize that denominator if you want...
