1. 9.4 Points, Lines and Planes of Solids
Additional Example 4
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2. Additional Example 4
In the figure, ABCDEF is a triangular prism. M and O are the mid-points of EF and DC respectively.
(a) Name the projections of AM and AF on the plane ABCD.
Solution
(b) Name the angle between the plane ABCD and the line
(i) AF,
(ii) AM.
Solution
(c)　 Name the angle between the planes EFBA and ABCD.
Solution
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3. Solution (a) The projection of AF on the plane ABCD is AC.
Additional Example 4
In the figure, ABCDEF is a triangular prism. M and O are the mid-points of EF and DC respectively.
(a) Name the projections of AM and AF on the plane ABCD.
(b) Name the angle between the plane ABCD and the line
(i) AF, (ii) AM.
(c)　Name the angle between the planes EFBA and ABCD.
Solution
(a) The projection of AF on the plane ABCD is AC.
The projection of AM on the plane ABCD is AO.
Q4(b)
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4. Solution (b) The angle between AF and the plane ABCD is FAC.
Additional Example 4
In the figure, ABCDEF is a triangular prism. M and O are the mid-points of EF and DC respectively.
(a) Name the projections of AM and AF on the plane ABCD.
(b) Name the angle between the plane ABCD and the line
(i) AF, (ii) AM.
(c)　Name the angle between the planes EFBA and ABCD.
Solution
(b) The angle between AF and the plane ABCD is FAC.
The angle between AM and the plane ABCD is MAO.
Q4(c)
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5. Additional Example 4
In the figure, ABCDEF is a triangular prism. M and O are the mid-points of EF and DC respectively.
(a) Name the projections of AM and AF on the plane ABCD.
(b) Name the angle between the plane ABCD and the line
(i) AF, (ii) AM.
(c)　Name the angle between the planes EFBA and ABCD.
Solution
(c) The angle between plane EFBA and the plane ABCD is FBC (or EAD).
© SNP Panpac (H.K.) Ltd.