Question 29459
distance = {{{-16t^2+112t}}}, so we have
{{{160 = -16t^2+112t}}}


so {{{0 = -16t^2+112t-160}}}
or {{{ 16t^2-112t+160 = 0 }}}
or {{{ t^2-7t+10 = 0 }}}


then factorise... 5 and 2 etc.


you will get 2 answers. What does getting 2 times mean physically?


jon.