( 2 4)2 x + = form ( ) ( ) f x a x h k = − + −8 2 ( 4)2 x + = a  x (−1) = − −4 + (−3) 2 Because the solutions to the equation are imaginary, we know that there are no ( 3) x–intercepts. a x = + −1 (−2, We use the point on the graph to determine −3) (−2 3)2 a −3 = + −1 the value of a: (1)2 a −3 = −1 a −3 = −1 a −2 = ( ) ( 3)2 f x a x = + −1 Thus, the equation of the parabola is ( ) ( 3)2 . f x x = −2 + −1
2 ( x + 4)2 = −8 form f ( x ) = a ( x − h ) + k 2 ( x + 4)2 = −4 = a  x − (−3) 2 + (−1) Because the solutions to the equation are imaginary, we know that there are no x–intercepts. = a ( x + 3) −1 We use the point (−2, −3) on the graph to determine the value of a: f ( x ) = a ( x + 3)2 −1 −3 = a (−2 + 3)2 −1 −3 = a (1)2 −1 −3 = a −1 −2 = a Thus, the equation of the parabola is f ( x ) = −2 ( x + 3)2 −1 .
Precalculus-Essentials-5th-Edition-Blitzer-Solutions-Manual.docx