Answer:
Step-by-step explanation:
we know that
The formula of law of cosines is equal to
where
a, b and c are sides. C is the angle opposite side c
In this problem we have
substitute the given values
Answer:
b) 24
Step-by-step explanation:
We solve building the Venn's diagram of these sets.
We have that n(S) is the number of succesful students in a classroom.
n(F) is the number of freshmen student in that classroom.
We have that:
In which n(s) are those who are succeful but not freshmen and 
are those who are succesful and freshmen.
By the same logic, we also have that:
The union is:
In which
So
So the correct answer is:
b) 24
The answer is 110.
The 55 degree angle is related to arc B. The measure of arc B is double the measure of the angle. So, arc B covers 55*2=110 degrees.
Answer:
The height of the triangle is 7cm and the base is 16cm
Step-by-step explanation:
First of all we have to know the formula to calculate area of a triangle
a = area = 56
b = base
h = heigth
a = (b * h)/2
we replace the known values and we make 2 equations
56cm² = (b * h)/2
b = h + 9cm
we replace b by (h + 9cm) in the first equation
56cm² = (h + 9cm * h)/2
56cm² * 2 = h² + 9h
0 = h² + 9h - 112cm²
we use bhaskara formula:
(-b (±) √
(b² - 4ac) ) / 2a
we replace with the known values
h = (-9 (±) √
(9² - 4*1*(-112) ) ) / 2*1
h = (-9 (±) √
(81 + 448) ) ) / 2
h = (-9 (±) √529) /2
h = (-9 (±) 23)/2
h1 = (-9 + 23) / 2
h1 = 14 / 2
h1 = 7
h2 = (-9 - 23) / 2
h2 = -32 / 2
h2 = -16
The height of the triangle is 7cm and the base is 16cm
