SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Explain the formula to use
Using the cosine rule which states that:

STEP 2: Write the given sides

STEP 3: Find the value of z

Hence, the indicated length is 4.0
Answer:
3z(2x - 3)
Step-by-step explanation:
Area of a rectangle, a = height * width
height, h = 3z
width, w = 2x - 3
a = 3z * (2x -3)
expand
a = 6xz - 9z
a = 3z(2x - 3)
x+2 > 10 solves to x > 8 after we subtract 2 from both sides
So set A is the set of real numbers that are larger than 8. The value 8 itself is not in set A. The same can be said about 5 as well.
Set B is the set of values that are larger than 5 since 2x > 10 turns into x > 5 after dividing both sides by 2. The value x = 5 is not in set B since x > 5 would turn into 5 > 5 which is false. The values x = 6, x = 8, and x = 9 are in set B.
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Summarizing everything, we can say...
5 is not in set A. True
5 is in set B. False
6 is in set A. False
6 is not in set B. False
8 is not in set A. True
8 is in set B. True
9 is in set A. True
9 is not in set B. False