alternative if you consider ax^2+bx+c=0 being a=2 B=1 c=-21 the new x = x^1/2...the solution is 3 and -14/4 that expected to be elevated ^2 = 3 and 12.25
If the x under the radical were negative (-3.5) and the other x was positive (24.50) it would work, which means that value under the square root was not the principle square root and that’s where it went wrong and the value was extraneous.
alternative if you consider ax^2+bx+c=0 being a=2 B=1 c=-21 the new x = x^1/2...the solution is 3 and -14/4 that expected to be elevated ^2 = 3 and 12.25
If the x under the radical were negative (-3.5) and the other x was positive (24.50) it would work, which means that value under the square root was not the principle square root and that’s where it went wrong and the value was extraneous.