SOLUTION: I just wanted to see if I have this expression written correctly for the following question: Thomas rowed upstream at 6 mph and downstream at 12 mph. If Thomas rowed for thre h

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Question 699846: I just wanted to see if I have this expression written correctly for the following question:
Thomas rowed upstream at 6 mph and downstream at 12 mph. If Thomas rowed for thre hours, how far was his entire trip, upstream and downstream?
I wrote the equation as: 6x + 12 (3-x). Is this correct?
Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Thomas rowed upstream at 6 mph and downstream at 12 mph. If Thomas rowed for three hours, how far was his entire trip, upstream and downstream?
:
Let d = the distance up or down stream
:
write a time equation, time = dist/speed
:
time up + time down = 3 hrs
d%2F6 + d%2F12 = 3
multiply by 12 to clear the denominators, find d, total dist = 2d

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +d+ = the one-way distance he rowed in miles
Let +t+ = his time going upstream in hrs
given:
(1) +d+=+6t+
(2) +d+=+12%2A%28+3+-+t+%29+
--------------------
Substitute (1) into (2)
(2) +6t+=+12%2A%28+3+-+t+%29+
(2) +6t+=+36+-+12t+
(2) +18t+=+36+
(2) +t+=+2+
+3+-+t+=+3+-+2+
+3+-+t+=+1+
------------
(1) +d+=+6t+
(1) +d+=+6%2A2+
(1) +d+=+12+
and
(2) +d+=+12%2A%28+3+-+t+%29+
(2) +d+=+12%2A%28+3+-+2+%29+
(2) +d+=+12%2A1+
(2) +d+=+12+
His distance for the trip was +2d+ or 24 mi
What you did was right. You just had to
make the 2 distances equal to each other.