h=- -t^2+16t-4
h=-(-t^2)+16t-4
h=t^2+16t-4
x=(-b+-sqrt(b^2-4ac))/(2a)
color(blue)(a^2+bx+c
color(blue)(a=1,b=16,c=-4
h=(-(16)+-sqrt((16)^2-4(1)(-4)))/(2(1))
(-16+-sqrt(256+16))/2
(-16+-sqrt(272))/2
(-16+-sqrt(2*2*2*2*17))/2
color(blue)(sqrt2 xx sqrt2=2
(-16+-4sqrt17)/2
(cancel4^color(blue)2(-4+sqrt17))/cancelcolor(blue)2^color(blue)1 or (cancel4^color(blue)2(-4-sqrt17))/cancel2^color(blue)1
2(-4+sqrt17) or 2(-4-sqrt17))
color(blue)(-8+2sqrt17 or -8-2sqrt17