Solve for x, given the equation square root of x minus 5 + 7 = 11. x = 21, solution is extraneous x = 21, solution is not extraneous x = 81, solution is extraneous x = 81, solution is not extraneous

This is the concept of algebra, to solve the expression we proceed as follows:
√(x-5)+7=11
put like terms together:
√(x-5)=11-7
√(x-5)=4
squaring both sides we get:
x-5=16
x=16+5
x=21
The solution is not extraneous.