Question 1168128
<pre>
v, the gallons that first car used
 

            fuel efficency     volume        miles
Firstcar       40                v           40v
Secondcar      25               45-v         25(45-v)
Totals                          45           1575
</pre>
First solve for first car's fuel volume used v, in gallons:
{{{40v+25(45-v)=1575}}}

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