34.8k views
5 votes
What is (x+3) (x-7)?

User Quaffel
by
6.6k points

2 Answers

4 votes

Answer:


x^2-4x-21

Explanation:


\left(x+3\right)\left(x-7\right)

Apply FOIL method:-


\left(a+b\right)\left(c+d\right)=ac+ad+bc+bd


\left(x+3\right)\left(x-7\right)


xx+x\left(-7\right)+3x+3\left(-7\right)


=x^2-4x-21

OAmalOHopeO

User Florian Drawitsch
by
7.8k points
5 votes

Answer:

We can use FOIL to solve this:

F - First

O - Outer

I - Inner

L - Last


= (x * x)+(x * - 7)+(3 * x)+(3 * - 7)


= {x}^(2) + - 7x + 3x - 21


= {x}^(2) - 4x - 21

User Ashish Awaghad
by
7.7k points