Question

expand using the formula (9p - 5r)(9p + 3r)​

Answer 1

Answer:

81p^2-18pr-15r^2

Step-by-step explanation:

(9p - 5r)(9p + 3r)​

9p[9p+3r]-5r[9p+3r]

81p^2+27pr-45pr-15r^2

81p^2-18pr-15r^2

Answer 2

Answer:

81p^2 -18pr -15r^2

Step-by-step explanation:

using (x+a) (x+b) =(x)^2 + (a+b)x + ab

(9p -5r) (9p +3r) = (9p)^2 + (-5r+3r)(9p)+ (-5r)×(3r)

=81p^2 -18pr -15r^2.