I need help finding the axis of symmetry. f(x)= −2(x − 4)2 + 2
@E.ali
is that -2(x-4)^(2) + 2
Yes, sorry about that f(x)= −2(x − 4)^2 + 2
given a vertex: (p,q) the axis of symmetry is defined as x=p you have a vertex form of a quadratic .... can you spot the x part?
if you expand it all out to the ax^2 + bx + c form .... the axis can be defined as: -b/(2a)
2x-8^2 + 2 x=2 -b/(2a) = -8/(2)2 -8/(2)2 = -8/4 -8/4=-2
i think your calcs are in error
square first, then distribute
−2(x − 4)^2 + 2 −2(x^2-8x +16) + 2 etc ...
-b/(2a) = -16/(2)2 -16/(2)2 = -16/4 -16/4=-4?
−2(x^2-8x +16) + 2 -2x^2-16x-32+2?
-2x^2-16x-30 -4x-16x-30 -20x-30?
@amistre64
-2x^2-16x-30 this is good, now -b = --16 2a = 2(-2) what does that simplify to?
-b=16 2a=-4
doh!! -2(-8) = 16 .... not -16
-16/-4 = 4
-2x^2 +16x -30 this is good, now -b = -16 2a = 2(-2) -16 ---- = 4, thats the axis -4
Thanks, could you help me find the axis of symmetry for g(x) = 5x2 − 10x + 7 as well?
Join our real-time social learning platform and learn together with your friends!