Answer: 52.5
Step-by-step explanation: 2(3x+10)+2(x+10)=360 because all the sides of a rhombus equal 360 and alternate sides are equal
8x+20=360
-20=-20
8x/8=340/8
x=42.5
x+10. 42.5+10=52.5
D=52.5
Answer:
a² - b² = 1
Step-by-step explanation:
The given parameters are;
sec 50° = a
cot 40° = b
We note that sec(θ) = 1/cos(θ) and cot(θ) = 1/tan(θ)
a² - b² = sec²50° - cot²40°
Given that sec(90 - θ) = cosec(θ) where; cosec(θ) = 1/sin(θ), we have;
sec²50° - cot²40° = sec²(90° - 50°) - cot²40° = sec²(40°) - cot²40°
sec²(40°) - cot²40° = cosec²(40°) - cot²40°
Also we have;
cosoc²(θ) = 1 + cot²(θ)
Therefore, we have;
cosoc²(40°) - cot²40° = 1 + cot²(40°) - cot²40° = 1
Therefore, where sec(50°) = a and cot(40°) = b, the value of a² - b² is 1.
Answer:

Step-by-step explanation:
Given Equations:
Equation:1
Equation:2
Multiplying Equation:2 by '7' both sides:
Equation:3
Subtracting Equation:3 from Equation:1

Dividing by '26' both sides:

Putting the value of 'y' in Equation:2

Adding '27' both sides:

Dividing by '2' both sides:

The values are:

Answer:
2/3
Step-by-step explanation:
this is the chance and answer
Answer:
c is the answer because the average in the final exam with lectures are higher than the average of case studies which proves that lectures are more effective than case studies.