Question

Find the axis of symmetry of the parabola formed by the following quadratic function:

y =-5x^2+7x-9

A. x = -7/5
B. x = 7/5
C. x = -7/10
D. x = 7/10

Answer 1

first divide through by -5
then convert to vertex form

Answer 2

how do i do that ? @cwrw238

Answer 3

divide by -5
;-

=-5(x^3 -7x/5 + 9/5)

= -5 ((x - 7/10)^2 +9/5 - 49/100))

x = 7/10 is the axis of symmetry

Answer 4

another way to do this is to use the formula x = -b/2a

from the general form a^x^2 + bx + c = 0

b = 7 and 2a = 2*-5 = -10

x = -7/-10
x = 7/10