Answer:
part b)
increasing: hour 1
constant: hours 2 and 4
decreasing: hours 3 and 5
part c)
non-linear
Step-by-step explanation:
600 increased by 20% = 600 * 1.2 = 720
720 decreased by 20% = 720 * 0.8 = 576
600 is larger by 24.
Answer:
Step-by-step explanation:
Given
Direct variation implies that:
Where k is the constant of variation.
Required
Find y when 
Make k the subject
For:
For:
becomes
Substitute
Make y the subject
9514 1404 393
Answer:
-7/4 < x < 8
Step-by-step explanation:
The value of y can be determined from the sum of the angles, so you know each of the angles exactly. That means you know the ratio of side lengths exactly, which lets you solve for x exactly.
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Setting that aside, we observe that angle C is greater than angle A, so side AB will be longer than side BC.
3x +15 > 4x +7
8 > x . . . . . . . . . . subtract 3x+7
We also know that the lengths of these sides must be positive. Since BC is the shorter side, we require ...
4x +7 > 0
4x > -7
x > -7/4
So, the allowable values of x are ...
-7/4 < x < 8
_____
<em>More complete solution</em>
If we read the figure correctly, the sum of angles is ...
(2y +12) +(4y +12) +(y -18) = 180
7y +6 = 180
y = (180 -6)/7 = 24 6/7°
Then (in degrees) ...
∠A = 2(24 6/7) +12 = 61 5/7, and ∠C = 4(24 6/7) +12 = 111 3/7
The Law of Sines tells us ...
AB/sin(C) = BC/sin(A)
sin(A)(3x +15) = sin(C)(4x+7)
x(4sin(C) -3sin(A)) = 15sin(A) -7sin(C)
x = (15sin(A) -7sin(C))/(4sin(C) -3sin(A))
x ≈ 6.1872652
You can use the quadratic formula:
X = (-b +/- ✓b^2 - 4ac)/2a
You then can get:
X = 2 or 1.5
Hope this helps! :)
