Rosy wants a large picture window. It has a area of 49 . How long is each side?

Hi Didi;

I am assuming that the window is a perfect square.

x=one side

x

^{2}=49+/-x=√49

+/-x=7

x=7 or -7, -7 is not a measurement.

x=7

You asked about "roots". We can do this more elaborately...

x

^{2}-49=0(x+7)(x-7)=0

Either parenthetical equation must equal zero.

x+7=0

x=-7, not applicable.

x-7=0

x=7