How can you estimate square roots without a calculator?

Can some one me, i’ve been asking for so long

Which equation represents a circle with a center at (–3, –5) and a radius of 6 units? (x – 3)2 + (y – 5)2 = 6 (x – 3)2 + (y – 5)2 = 36 (x + 3)2 + (y + 5)2 = 6 (x + 3)2 + (y + 5)2 = 36

The larger of two number is 4 less than twice the smaller number. the sum is 41. find the numbers