Find the vertex of the parabola $y = x^2 - 2x - 3$.
A$(0, -3)$
B$(1, -4)$
C$(-1, 0)$
D$(2, -3)$
Answer & Solution
Correct answer: B. $(1, -4)$
Factoring gives $(x - 3)(x + 1) = 0$, so the x-intercepts are $-1$ and $3$. The axis of symmetry sits midway, at $x = 1$. Substitute $x = 1$ into $y = x^2 - 2x - 3$: $y = 1 - 2 - 3 = -4$. So the vertex is $(1, -4)$. Option A is the y-intercept, not the vertex.
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