Answer:
(x, y, z) = (-4, 2, 1)
Step-by-step explanation:
See the attachment for the output of a calculator that produces the reduced row-echelon form of the matrix.
The [x, y, z] result vector is the column on the right.
(x, y, z) = (-4, 2, 1)
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Numerous web sites are available for computing the row-reduced form of the matrix, or for solving the system of equations. Your graphing calculator will do it as well.
Note that
108° = 90° + 18°
so
sin(108°) = sin(90° + 18°) = sin(90°) cos(18°) + cos(90°) sin(18°) = cos(18°)
Then
sin²(108°) + sin²(18°) = cos²(18°) + sin²(18°) = 1
by the Pythagorean identity.
Use these formulas to get the surface area and volume. Hopes this helps! ❤️