00:01
So for this question, we want to solve the systems of equations using substitution.
00:06
So we have decimals and fractions.
00:08
So it will be easier to multiply each equation by something so that we can get whole numbers instead.
00:15
So let's start with the first equation, right? in this case, what can we multiply to get whole numbers? so because we have a decimal and it's in the 10th place, we want to multiply by 10.
00:27
So we're going to multiply the entire top equation by 10.
00:32
So let me just go ahead and write that down.
00:35
We're going to multiply this entire section by 10.
00:39
And then for the bottom section, we have fractions where the denominator is 3, right? so to get rid of the denominator, we want to multiply the entire equation by 3 so that the denominator will cancel out.
00:52
So if we multiply this entire equation by 3 and the top 1 by 10, it'll be much easier to solve.
00:58
So this is kind of how our new systems of equation is going to look like.
01:04
So 0 .3a times 10, that's just going to be 3a, right, plus 1b equals 5.
01:12
And then for the bottom one, we have 4a plus b equals 9.
01:19
That's kind of how our systems of equation is going to look like...