I'll do part (a) to get you started.
The angle 'a' pairs up with the 123 degree angle as a corresponding angle pair. Due to the parallel lines, the corresponding angles are congruent. Therefore a = 123.
We also see that b = 123 as well since a = b (they are vertical angles).
Notice how angle c is adjacent to the 123 degree angle. These two angles form a straight line, so they must add to 180 degrees.
c+123 = 180
c = 180-123
c = 57
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To summarize, we have these three angles
a = 123
b = 123
c = 57
your answer would be 9 fish are left in the tank
The function
... f(x) = (x+2)/(x-1) = 1 + 3/(x-1)
is symmetrical about the line y=x, hence is its own inverse.
We can evaluate the desired derivative directly.
... f'(x) -3/(x-1)²
so f'(2) is
... f'(2) = -3/(2-1)²

Answer:
D Multiply equation B by 5 and equation A by 4 and add the results together
Discount =5%
Regular price =$83
Price at which daniel bought the shorts =$83-5%of$83
=$83-5×83/100
=$78.85