How do you find the x-intercepts and the vertex of the parabola:
\[ y = -x^2 - 5x \]?
Answer (2)
− x 2 − 5 x = 0 − x ( x + 5 ) = 0 x = 0 ∨ x = − 5
The x-intercepts are ( 0 , 0 ) and ( − 5 , 0 ) .
vertex = ( h , k ) h = 2 x 1 + x 2 , k = y ( h ) h = 2 0 − 5 = 2 − 5 = − 2.5 k = y ( − 2.5 ) = − ( − 2.5 ) 2 − 5 ⋅ ( − 2.5 ) k = − 6.25 + 12.5 k = 6.25 vertex = ( 2.5 , 6.25 )
The x-intercepts of the parabola y = − x 2 − 5 x are (0, 0) and (-5, 0). The vertex of the parabola is at the point (-2.5, 6.25).
;
