7cos(x) + 1 = 6sec(x)
7cos(x) + 1 = 6/cos(x)
7cos^(x) + cos(x) = 6
7cos^(x) + cos(x) - 6 = 0
[7cos(x) - 6][cos(x) + 1] = 0
cos(x) = 6/7 , x = arccos(6/7) and
cos(x) = -1, x = 180
X^2 - 13 x = -36
add 36 to both sides
x^2 - 13x +36 = 0
figure out the factor
(x-4)(x-9) = 0
so (x-4) or (x-9) equals 0
so solution is
x-4=0 add 4 to both sides and get x = 4
x-9=0 add 9 to both sides and get x=9
x={ 4, 9}
1.3 million stocks was there in beginning of the day
surface area = 4 x pi x r^2
diameter = 1 so radius = 1/2 = 0.5
4 x 3.14 x 0.5^2 = 3.14 meters^2
Area of the trapezium = 1/2 (40 + 160) x 70
Area of the trapezium = 7000 ft²
One bag of fertilizer = 4000 ft²
Number of bags of fertilizer needed = 7000 ÷ 4000 = 1.75 bags.
Since only full bags of fertilizer can be bought, 2 bags of fertilizer are needed.
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Answer: 2 bags of fertilizer
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