I need help with this math question

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

What properties allow transformation to be used as a problem solving tool

Solve this equation using substitution. {4x + y = −2} {4x + 6y = 44}