Answer:

Step-by-step explanation:
So the number of questions in an exam varies with the number of minutes to take the exam.
For each question there are 5 minutes allotted.
Lets say that there are 'x' number of questions in the exam and 't' is the total time taken to finish the exam, in minutes. So the time taken to complete the exam would be

Therefore, the equation relating the time taken to complete the exam and the number of questions is given by:

So there are two variables in the equation, 't', and 'x':
t - time taken to complete the exam
x - number of questions on the exam
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.
__
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
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<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
Answer:

Step-by-step explanation:
8x+9=0
8x=-9

or

,



, 
For this case we have that by definition
equals 180 degrees.
We must convert 135 degrees to radians, then:

Rounding off we have:
2.4 radians.
Answer:
2.4 radians