If a+b=−9, and a=30/b, what is the value of a^2+b^2?
Choose the most appropriate option:
A) 31
B) 21
C) 41
D) 61
E) 51

Rationale: "a ^ 2 + b ^ 2 should make you think of these formulas : ( a + b ) ( a + b ) = a ^ 2 + b ^ 2 + 2 ab we already know ( a + b ) = - 9 and a * b = 30 ( a + b ) ( a + b ) = ( - 9 ) ( - 9 ) = a ^ 2 + b ^ 2 + 2 * ( 30 ) a ^ 2 + b ^ 2 = 81 - 60 = 21 answer : b"
Answer: B