00:01
This problem asks us to solve this system of equations.
00:06
And first i want to show you substitution.
00:11
So for substitution, i'm going to take the first equation.
00:16
And if you subtract 4b from both sides, then you can get a on its own.
00:24
So then a equals 6 minus 4b.
00:27
Then you can plug this into the second equation for a.
00:31
So that becomes 3 times 6 minus 4b plus 2b equals negative 2.
00:39
You need a factor over the 3.
00:42
You get 18 minus 12b plus 2b equals negative 2.
00:50
This simplifies to 18 minus 10b equals negative 2.
00:55
Subtract 18 on both sides.
00:58
Get negative 10b is equal to negative 20.
01:02
Divide by negative 10 on both sides in order to get b alone, and that gives us that b is equal to 2.
01:11
Then plug this back into the equation up here, and we get a plus 4 times 2 is equal to 6...