Grade 9 math · C.2 · Functions
Evaluate quadratic functions
Square the number first, then multiply.
See worked examples
f(x) = 3x² + 5x. Find f(−5).
Answer: 50
f(x) = 2x² + 5x − 9. Find f(1).
Answer: -2
f(x) = −x² − 2x + 11. Find f(−4).
Answer: 3
Tip: Square the number first, then multiply.
Curriculum
Common Core: HSF-IF.A.2, HSF-IF.B.6
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