The area of each face is 25 cm
First solve for theta in 'x' equation:
Substitute into 'y' equation:
Simplify by rewriting cos in terms of sine.
Using pythagorean identity:
Simplify using inverse function property:
Plug in "8i + 15j + k" for "f", and "2i – 5j + 9k" for "e"
3(8i + 15j + k) - 2(2i – 5j + 9k)
Distribute 3 to (8i + 15j + k) & - 2 to (2i – 5j + 9k)
3(8i + 15j + k) = 24i + 45j + 3k
-2(2i - 5j + 9k) = -4i + 10j - 18k
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Simplify. Combine like terms
24i - 4i + 45j + 10j + 3k - 18k
(24i - 4i) + (45j + 10j) + (3k - 18k)
20i + 55j - 15k is your answer, or (C)
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hope this helps
OK. I used my calculator to evaluate sec(85 degrees).
My calculator doesn't have a "sec" button on it.
But I remembered that
sec of an angle = 1 / (cosine of the same angle) .
So I used my calculator to find cos(85), and then I hit the
" 1/x " key, and got 11.474, which I knew to be sec(85).
Answer:
9A-F
9B-EI
9C-FG
Step-by-step explanation:
