could someone help me with math?

Question

Multiply.

(x-6)(x-2)(x-5)

 

I'm so confused. I'm used to doing just doubles. but what do you do if they're triple? 

Answer 1

Hello, thank you for taking the time to post your question!

I would do the first two terms using FOIL, then do the distributive property for the last one

(x – 6)(x – 2) = x^2 – 8x + 12

(x^2 – 8x + 12)(x – 5)

=x^3 – 13x^2 + 52x - 60

I hope that helps get you moving in the right direction! Feel free to reach out if you have any additional questions beyond that :)

Answer 2

You are just using the distributive property over and over. Using the distributive property  to distribute the second two terms into the first one you can re-write it like this.

x(x-2)(x-5) - 6(x-2)(x-5)

 

Now you can use your normal method to multiply the other two and get x² - 7x + 10 and the whole thing becomes

x(x² - 7x + 10) - 6(x² - 7x + 10)  

 

Distribute the x and the -6

(x³ - 7x² + 10x) + (-6x² + 42x - 60)

 

Combine like terms and your done

x³ - 13x² + 52x - 60