Answer:
60°
Step-by-step explanation:
they are equal.....
To solve for this, we need to find for the value of x
when the 1st derivative of the equation is equal to zero (or at the
extrema point).
So what we have to do first is to derive the given
equation:
f (x) = x^2 + 4 x – 31
Taking the first derivative f’ (x):
f’ (x) = 2 x + 4
Setting f’ (x) = 0 and find for x:
2 x + 4 = 0
x = - 2
Therefore the value of a is:
a = f (-2)
a = (-2)^2 + 4 (-2) – 31
a = 4 – 8 – 31
a = - 35
Let the marks of the students in class 1 be

the average of these 12 marks is 90, so

which means

similarly, let

be the marks of the students in the second class,
so

which means

The 32 students averaged:
First, take all the sides you already have, then add them up. (You should get 12) To find the other two sides, do some more simple addition. The 2+3+2 of the the top side add up to six (the bottom side) and sides equal each other so add another three. Total is 12+6+3=21
Obtuse and isosceles
Isosceles means that at least two of the sides are congruent or equal.
Obtuse means that one angle of the triangle is greater than 90 degrees.
So, your answer is D and E
:)))