equate the quadratic equation. X squared minus three x minus 28 equals zero. And we're going to do this by factoring Well, since are a coefficient is one. We can go straight into the fact drink. So that means we need to find two factors of negative 28 that when I add them together, give me negative three. Well, let's start by listing Are factors Well, since we know that our the factors super haven't give us a negative product, one has to be negative. One has to be positive. And since our some is negative, the larger number is gonna be negative. So we're let's do 28 positive one that give me 28 when a multiply. But they gave me negative 27 when I asked, So let's move on to two. So that would be negative. 14. And to they give me negative 28 when I multiply, but they give me negative 12 when I add. Three will not go into 28. So let's go into four. So that would be negative. Seven and four negative seven times four. Give me negative 28 when I add them, they give me Negative three. So right here are my two factors I'm gonna be using. So I'll have X minus seven and X plus four and both of them all equal zero. So now that I know both says the factors we can go ahead and make up. Each equals zero. So X minus seven equals zero X plus four equals zero and we can solve for X. So we add seven to bust sods. An ex would equal seven and then we would subtract four on both sides. An ex would equal negative four. So my two solutions would be negative for and seven.

## Comments

## Video Transcript

equate the quadratic equation. X squared minus three x minus 28 equals zero. And we're going to do this by factoring Well, since are a coefficient is one. We can go straight into the fact drink. So that means we need to find two factors of negative 28 that when I add them together, give me negative three. Well, let's start by listing Are factors Well, since we know that our the factors super haven't give us a negative product, one has to be negative. One has to be positive. And since our some is negative, the larger number is gonna be negative. So we're let's do 28 positive one that give me 28 when a multiply. But they gave me negative 27 when I asked, So let's move on to two. So that would be negative. 14. And to they give me negative 28 when I multiply, but they give me negative 12 when I add. Three will not go into 28. So let's go into four. So that would be negative. Seven and four negative seven times four. Give me negative 28 when I add them, they give me Negative three. So right here are my two factors I'm gonna be using. So I'll have X minus seven and X plus four and both of them all equal zero. So now that I know both says the factors we can go ahead and make up. Each equals zero. So X minus seven equals zero X plus four equals zero and we can solve for X. So we add seven to bust sods. An ex would equal seven and then we would subtract four on both sides. An ex would equal negative four. So my two solutions would be negative for and seven.

## Next Lectures