Question 1135051

julie recently drove to visit her parents who live 240 miles away. on her way there her average speed was 11 miles per hour faster than on her way home (she ran into some bad weather). if julie spent a total of 8 hours driving, find the two rates
<pre>Let speed to destination be S
Then return speed = S - 11
We then get the following TIME equation: {{{matrix(1,3, 240/S + 240/(S - 11), "=", 8)}}}
240(S - 11) + 240S = 8S(S - 11) ------- Multiplying by LCD, S(S - 11)
{{{matrix(1,3, 240S - "2,640" + 240S, "=", 8S^2 - 88S)}}}
{{{matrix(1,3, 480S - "2,640", "=", 8S^2 - 88S)}}}
{{{matrix(1,3, 8S^2 - 88S - 480S + "2,640", "=", 0)}}}
{{{matrix(1,3, 8S^2 - 568S + "2,640", "=", 0)}}}
{{{matrix(1,6, 8(S^2 - 71S + 330), "=", "8(0)_____", S^2 - 71S + 330, "=", 0)}}}
(S - 66)(S - 5) = 0
{{{highlight_green(matrix(2,7, Outgoing, speed, or, S, "=", 66, mph, Return, speed, or, S - 11, "=", 55, mph))}}}         OR           {{{matrix(1,5, S, "=", 5, mph, "(ignore)")}}}