(I tried to post this earlier but couldn't for some reason.)
#Turning points question.(S.A.T.)
split obsidian
bright cedarBOT
crimson sequoia
write it in vertex form y = a(x-9)^2-14
in standard form it is y = ax^2 + bx + c notice x = 1 gives a+b+c.
==> a+b+c = a(1-9)^2-14 = 64a-14
now u can use b^2-4ac > 0 since it intersects 2 points to get that a>0.
or if u think about it a > 0 b/c it opens up in order to intersect x axis at 2 points.
so a>0 ==> 64a>0 ==> 64a-14> -14
therefore, a+b+c > -14 ==> (D) -12 is the only choice
split obsidian
write it in vertex form y = a(x-9)^2-14
in standard form it is y = ax^2 + bx + c...
Oh, thanks again!
.close