What is the axis of symmetry and vertex for the graph #y= -7x^2 +2x#?

1 Answer
Jul 7, 2018

#x=1/7," vertex "=(1/7,1/7)#

Explanation:

#"calculate the zeros by letting y = 0"#

#-7x^2+2x=0#

#x(-7x+2)=0#

#x=0,x=2/7larrcolor(blue)"are the zeros"#

#"the vertex lies on the axis of symmetry which is"#
#"situated at the midpoint of the zeros"#

#"axis of symmetry "x=(0+2/7)/2=1/7#

#"substitute this value into the equation for y-coordinate"#

#y=-7(1/7)^2+2(1/7)=-1/7+2/7=1/7#

#color(magenta)"vertex "=(1/7,1/7)#
graph{-7x^2+2x [-10, 10, -5, 5]}