quadratic functions 9 1 answer key
tex of \(f(x) = 2x^2 + 8x + 3\). Solution: Use vertex formula: \[ x_v = -\frac{b}{2a} = -\frac{8}{2 \times 2} = -\frac{8}{4} = -2 \] Calculate \(f(-2)\): \[ f(-2) = 2(-2)^2 + 8(-2) + 3 = 2(4) - 16 + 3 = 8 - 16 + 3 = -5 \]