ACT Math · Matrices and vectors
What is the magnitude of the vector (5, -12)?
What is the magnitude of the vector ?
Answer and explanation
Answer: F: 13
Magnitude = √(5² + (−12)²) = √(25+144) = √169 = 13. Choice G comes from adding the components directly instead of squaring them: 5 + (−12) = −7, then taking the absolute value. Choice H adds the absolute values of the components (5+12=17) instead of applying the distance formula. Choice J stops one step early, reporting 25+144=169 without taking the square root.
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