The answer is 20² + 6(9 + 3) = 472
Use PEMDAS:
P) Parentheses first
E) Exponents (For example, Powers and Square Roots.)
MD) Multiplication and Division
AS) Addition and Subtraction
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20² + 6 (9 + 3) = 400 + 6 (12) = 400 + 72 = 472
