Answer:
20
Step-by-step explanation:
We are given:
- Parallelogram CDEF
- ∠C = 13x - 10
- ∠D = 5x + 10
To Find: ∠E
Concept Used:
- Adjacent angles of a Parallelogram are Supplementary
Finding the value of 'x':
Since adjacent angles of a parallelogram are Supplementary:
∠D + ∠C = 180
5x + 10 + 13x - 10 = 180 [replacing the values of angle C and D]
18x = 180
x = 10 [dividing both sides by 18]
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Finding Measure of Angle D:
We are given that:
∠D = 5x + 10
∠D = 5(10) + 10 [since x = 10]
∠D = 60°
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Finding the measure of ∠E:
∠D and ∠E are Adjacent angles
Since Adjacent angles are Supplementary:
∠D + ∠E = 180
60 + ∠E = 180
∠E = 120° [subtracting 60 from both sides]
Hence, the measure of ∠E = 120°
ok but what's the question? u gave us info but what's the question
P + s = 200......p = 200 - s
20p + 15s = 3400
20(200 - s) + 15s = 3400
4000 - 20s + 15s = 3400
-20s + 15s = 3400 - 4000
-5s = - 600
s = -600/-5
s = 120 <=== there were 120 standard tickets sold
p + s = 200
p + 120 = 200
p = 200 - 120
p = 80 <=== there were 80 premium tickets sold
For this case we have the following system of two equations with two unknowns:

Adding both equations we have to eliminate the variable "x":

Adding common terms, keeping in mind that different signs are subtracted and the sign of the major is placed:

Answer:

Option A