SOLUTION: So it's d=r付 .... Two cars start from towns 665 miles apart and travel toward each other. They meet after 7hrs. Find the speed of each car if one travels 25 miles faster

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Question 907574: So it's d=r付 .... Two cars start from towns 665 miles apart and travel toward each other. They meet after 7hrs. Find the speed of each car if one travels 25 miles faster
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +d+ = the distance the
slower car travels in 7 hrs
+665+-+d+ = the distance the
faster car travels in 7 hrs
Let +s+ = the speed of the slower car
+s+%2B+45+ = the speed of the faster car
-------------------------------------
Equation for slower car:
(1) +d+=+s%2A7+
Equation for faster car:
(2) +665+-+d+=+%28+s+%2B+45+%29%2A7+
----------------------------
Add the equations
(1) +d+=+s%2A7+
(2) +665+-+d+=+%28+s+%2B+45+%29%2A7+
----------------------------
+665+=+7s+%2B+7s+%2B+315+
+14s+=+350+
+s+=+25+
and
+s+%2B+45+=+70+
-----------------
The slower cars speed is 25 mi/hr
The faster car's speed is 70 mi/hr
------------------------------
check:
(1) +d+=+s%2A7+
(1) +d+=+25%2A7+
(1) +d+=+175+
and
(2) +665+-+d+=+%28+s+%2B+45+%29%2A7+
(2) +665+-+d+=+70%2A7+
(2) +d+=+665+-+490+
(2) +d+=+175+
OK