00:01
All right here on this problem, we want to solve this system of equations by substitution.
00:06
Now let's start here on this left equation.
00:09
Here on this left equation, i'm going to add 2y to both sides.
00:16
And so this is going to tell me 5x is equal to negative 25 plus 2y.
00:26
Now if i multiply this all by 2, okay, multiply the whole equation by 2, we get 10x is equal to negative 50 plus 4 y.
00:42
10x is equal to negative 50 plus 4 y.
00:46
Now 10x is negative 50 plus 4 y.
00:48
So up here in the second equation, i can plug in negative 50 plus 4y for 10x.
00:57
And so that's what the left is going to give me negative 50 plus 4y.
01:02
Then here on the right, i have 3 times y minus 10.
01:06
And that's 3y minus 30 whenever we distribute that in.
01:13
And so now to solve this equation, let's subtract 3y on each side...