Step-by-step explanation:
[tex](7r+5s)^2[/tex]
use the pattern
[tex](a+b)^2=a^2+2ab+b^2[/tex]
[tex](7r+5s)^2=(7r+5s)(7r+5s)[/tex]
Apply FOIL method to multiply the parenthesis
[tex](7r+5s)^2=(7r+5s)(7r+5s)[/tex]
[tex](7r+5s)(7r+5s)\\49r^2+35rs+35rs+25s^2\\49r^2+70rs+25s^2[/tex]
Compare the expression with [tex](a+b)^2=a^2+2ab+b^2[/tex]
The value of a=7r and the value of b=5s
Answer :
a=7r , b=5s
