Answer:
700
Step-by-step explanation:
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
Answer:
2520cm²
Step-by-step explanation:
Surface area = sum of the area of all the bases.
Area of bottom base = 28 * 30 = 840
Area of right base = 25 * 30 = 750
Area of left base = 17 * 30 = 510
Area of two triangles = ( 15 * 28 ) / 2 = 210 * 2 = 420
Then add all the areas together to find surface area
Surface area = 840 + 750 + 510 + 420 = 2520cm²
Relevant Formulas:
Area of a rectangle = length * width. This formula was used to find the area of the bottom base, the right base and the left base
Area of a triangle = ( height * base length ) / 2 . This formula was used to find the area of the sides which are triangles.
First step to factor the trinomial, multiply the constant -28 with the leading coefficient 6.
So, -28 * 6 = - 168.
Next step is to breakdown -168 into two multiples so that their addition will result the coefficient of w= - 13.
So, -168 = -21 * 8.
And addition of - 21 and 8 will give - 13.
So, next step is to replace -13x with -21x + 8. Therefore,
6x² - 21x + 8x - 28 =0
(6x² - 21x) + (8x - 28 )=0 Make the group of two terms.
3x (2x - 7) + 4 (2x - 7) = 0 Take out the common factor from each group.
(2x - 7)(3x + 4) = 0 Again take out the common factor (2x -7).
So, 2x - 7 =0, 3x + 4 = 0 Set both the factor equal to 0.
2x = 7 , 3x = -4
So, 
Hope this helps you !
