SOLUTION: Thank you for answering my question: To find the height of a tree, Jack used a mirror placed on the ground. He moved it until he could see the top of the tree in the mirror. At

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Question 975000: Thank you for answering my question:
To find the height of a tree, Jack used a mirror placed on the ground. He moved it until he could see the top of the tree in the mirror. At this point, his eye was 1.2m above the ground and the distance between the mirror and him was 1.4m, while the distance between the mirror and the tree was 4.2m. Find the height of the tree.
If possible, please include a brief explanation! Thanks so much! :)
Found 2 solutions by josgarithmetic, jim_thompson5910:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Similar Triangles. Both are Right triangles. If you make a picture, identify corresponding parts,

The hypotenuses are the distances from mirror to Jack's eyes, and from mirror to top of tree. You will use the legs of the right triangles.

1.2%2Fy=1.4%2F4.2

y%2F1.2=4.2%2F1.4

y=%281.2%2A4.2%29%2F1.4

y=3.6

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
If you draw the picture, you'll find that 2 similar triangles form.

The sides of the triangle form this proportion 1.2%2F1.4+=+x%2F4.2

1.2%2F1.4+=+x%2F4.2


1.2%2A4.2+=+1.4x


5.04+=+1.4x


1.4x+=+5.04


x+=+5.04%2F1.4


x+=+3.6


So the tree is 3.6 meters tall
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