SOLUTION: Can someone please help me? How high is a tree that casts a 35-ft shadow at the same time a 4​-ft post casts a shadow which is 12​-ft ​long?

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Question 1039833: Can someone please help me?
How high is a tree that casts a 35-ft shadow at the same time a 4​-ft post casts a shadow which is 12​-ft ​long?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Think of the light rays coming down at
a certain angle. The thing that never changes
is the angle that the light ray makes when
it hits the ground.
-----------------
What does change is the length of the shadow
when something gets in the way of the
light ray, but all these obstructions create
similar triangles because ( height ) / ( shadow )
will stay the same
-----------------
Let +h+ = the height of the tree
-----------------
+h+%2F+35+=+4+%2F+12+
Multiply both sides by +12%2A35+
+12h+=+35%2A4+
+12h+=+140+
+h+=+11.667+
Convert +.667+ ft to inches
+.667%2A12+=+8+
The height of the tree is 11 ft 8 in