Chapter 4 - Quadratic Functions - 4.2 Graphing Quadratics in Vertex Form - 4.2 Exercises - Page 320: 50

Domain: All real numbers. Range: $y\leq 3$

Given $$ f(x) = -0.5(x+8)^2+3.$$ Student's work: Domain: All real numbers. Range: $ y\geq 3$ The domain is correct. The range indicates that the parabola faces upward. But the parabola opens downward. He should use a "less than or equal to" sign instead. Domain: All real numbers. Range: $y\leq 3$.