Question 102989
If you're concerned, always check your answer. 
You got d=29.4 miles
{{{Distance = Rate* Time}}}
Calculate {{{T[1]}}} and {{{T[2]}}}
{{{29.4 = 24*T[1]}}}
{{{29.4 = 18*T[2]}}}
{{{T[1]}}}= 1.225 hrs.

{{{T[2]}}}= 1.633 hrs.
{{{Total Time}}} = 2.858 hrs.,does not equal the 4.9 hr total. 
Distance =  Rate * Time
When traveling to the town
1. {{{D = 24*T[1]}}}
When traveling back from town
2. {{{D=18*T[2]}}}
You know that 
{{{T[1]+T[2]=4.9}}}
From equation 1, find a value for T[1]
1. {{{D = 24*T[1]}}}
{{{D/24 = cross(24)*T[1]/cross(24)}}} Multiplicative inverse of 24.
{{{T[1]=D/24}}}
From equation 2, find a value for T[2]
1. {{{D = 18*T[2]}}}
{{{D/18 = cross(18)*T[2]/cross(18)}}} Multiplicative inverse of 18.
{{{T[1]=D/24}}}
Plug those values into your total time equation,
{{{T[1]+T[2]=4.9}}}
{{{D/24+D/18=4.9}}}Substitute
{{{18D+24D=4.9*18*24}}} Multiply by the product of 18*24 to remove denominators.
{{{42D=4.9*18*24}}}Simplify.
{{{cross(42)D/cross(42)=4.9*18*24/42}}}Multiplicative inverse of 42
D=50.4 miles
Check your answer
1. {{{D = 24*T[1]}}}
{{{50.4=24*T[1]}}}
{{{T[1]=40.4/24}}}
{{{T[1]}}}=2.1 hrs.
2. {{{D = 18*T[2]}}}
{{{50.4=18*T[2]}}}
{{{T[2]=50.4/18}}}
{{{T[2]}}}=2.8 hrs.
{{{T[1]+T[2]=4.9}}}
Good answer.