intermediate algebra

[hopen2impov]

multiply

(5 -3r) (5 +3r)
25 +15r -15r -9r^2
25 -9r^2

 

[wjm11]

(5 -3r) (5 +3r)
25 +15r -15r -9r^2
25 -9r^2

Correct.

 

[hopen2impov]

Yeah, thank you for checking my work.

 

[mmm4444bot]

(5 -3r) (5 +3r)

In time, you'll recognize this factorization pattern as the factorization for a difference of squares.

You can then immediately write the difference of the two squares.

5^2 - (3r)^2

which is the same as 25 - 9r^2