If ##r = (23*5)/(x+7)##, what is ##r^2##?

##r=(23*5)/(x+7)=115/(x+7) => r^2=115^2/(x+7)^2=13225/(x^2+14x+49)## ##=(23^2*5^2)/(x+7)^2##

##r=(23*5)/(x+7) => r^2=((23*5)/(x+7))^2=(23*5)^2/(x+7)^2=((23)^2(5)^2)/((x+7)(x+7))##

##=((20+3)^2(25))/(x*x+7x+7x+7(7))##

##=(((20)(20)+(3)(20)+(3)(20)+(3)(3))(25))/(x^2+14x+49)##

##=((400+60+60+9)(25))/(x^2+14x+49)##

##=((400+120+9)(25))/(x^2+14x+49)=((529)(25))/(x^2+14x+49)##

##=((529)(20+5))/(x^2+14x+49)=(529(20)+529(5))/(x^2+14x+49)##

##=(2(5290)+5290(1/2))/(x^2+14x+49)=(10580+2645)/(x^2+14x+49)##

##13225/(x^2+14x+49)##