What is 23 + 4=x + 21

Hope it helps!

Are you learning about the simple square roots, as in square root of 36 for example? If so.. the best "trick" that I can think of to make it easier is if you know your multiplication pretty well, then it should be helpful.

Square root of 36 is 6 because 6 times 6 equals 36.
Square root of 49 is 7 because 7 times 7 equals 49.
Square root of 81 is 9 because 9 times 9 equals 81.
And so on.