In mathematical notation, ∑ means summation. So wherever you see the symbol, you have to sum over all elements in the set. Let's solve the question.
a. ∑m means, to sum all elements in the set m: ∑m = 12 + 15 + 20 + 30 = 77
b. ∑
means to sum all elements in the set f as the square of the elements f = 
c. ∑mf means to sum all elements as the product of the elements of m and f = (12×5) + (15×9) + (20
10) + (30×16) = 875
d. ∑
means to sum all elements as the product of the square of m and f = 
Answer:
57 deg
Step-by-step explanation:
Rhombus ABCD has diagonals AC and BD which intersect at point E.
The diagonals of a rhombus divide the rhombus into 4 congruent triangles.
If you find the measures of the angles of one of the triangles, then you know the measures of the angles of all 4 triangles.
Also, the diagonals of a rhombus are perpendicular.
Look at triangle BCE.
m<BCE = 33
m<BEC = 90
m<BCE + m<BEC + m<CBE = 180
33 + 90 + m<CBE = 180
m<CBE = 57
<ABE in triangle ABE corresponds to <CBE in triangle BCE.
m<ABE = m<CBE = 57
Answer: 57 deg
I believe its answer is D.
A function is a relation from a set of possible outputs where each input is related to exactly one output. I how this is what you're looking for.
Because the angels are equivalent, you can set the expressions equal to each other and solve. You will find that x = 54.
Work shown in image - let me know if I made any errors or if you have any additional questions.
