What is the vertex form of # f(x) = -5x^2-2x+9 #? Algebra Quadratic Equations and Functions Vertex Form of a Quadratic Equation 1 Answer Binayaka C. Feb 12, 2018 Vertex is # (-0.2 , 9.2)# and vertex form of equation is # f(x) = -5(x+0.2)^2+9.2 # Explanation: #f(x) = -5x^2-2x+9 or f(x) = -5(x^2+0.4x)+9# or # f(x) = -5(x^2+0.4x+(0.2)^2)+5*0.04+9# or # f(x) = -5(x+0.2)^2+9.2 #. Vertex is # (-0.2 , 9.2)# and vertex form of equation is # f(x) = -5(x+0.2)^2+9.2 # [Ans] Answer link Related questions What is the Vertex Form of a Quadratic Equation? How do you find the vertex form of a quadratic equation? How do you graph quadratic equations written in vertex form? How do you write #y+1=-2x^2-x# in the vertex form? How do you write the quadratic equation given #a=-2# and the vertex #(-5, 0)#? What is the quadratic equation containing (5, 2) and vertex (1, –2)? How do you find the vertex, x-intercept, y-intercept, and graph the equation #y=-4x^2+20x-24#? How do you write #y=9x^2+3x-10# in vertex form? What is the vertex of #y=-1/2(x-4)^2-7#? What is the vertex form of #y=x^2-6x+6#? See all questions in Vertex Form of a Quadratic Equation Impact of this question 1651 views around the world You can reuse this answer Creative Commons License