Step-by-step explanation:

Answer:
138 cm.
Step-by-step explanation:
So first, we find the S.A. of the front and back.
The diagram says the side length of the front is 3 cm. and 3 cm.
3x3=9. So then, the back is also 9 cm, 9+9=18.
Now to find the S.A.'s of the four sides, you have to see the side lengths of each of them. The side lengths are 3 and 10.
3x10=30. This means each of them is 30 cm.
30x4=120. 120 is the total surface area of the four sides.
To find the total surface area of the whole rectangle, you add all the surface areas.
120+18=138 cm. (Not squared, since it's surface area and not area.)
A whole number is always written as itself over one.
45/1
Answer: 45/1
The value of x from the given triangle is 32√3/3
<h3>SOH CAH TOA identity</h3>
In order to determine the value of x, first we need to determine the hypotenuse side of the smaller triangle.
sin 60 = 8√2/H
H = 8√2/sin60
H = 8√2 * 2/√3
H = 16√2/√3
H = 16√6/3
For the value of x, we will use the expression
sin45 = (16√6/3)/x
1/√2 = 16√6/3x
3x = 16√12
3x = 32√3
x = 32√3/3
Hence the value of x from the given triangle is 32√3/3
Learn more on SOH CAH TOA here: brainly.com/question/20734777
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