Answer:
x = 11
Step-by-step explanation:
∠BCE + ∠ECF = 180°
∴(10x + 15)° + 5x° = 180°
(15x + 15)° = 180°
15x = 180° - 15°
15x = 165°
x = 165°/15°
x = 11°
The surface area of the triangular prism is of 140 cm².
<h3>What is the surface area of a prism?</h3>
It is the sum of the areas of all faces of a prism. In this problem, the prism has these following faces:
- One rectangle of dimensions 8 cm and 6 + 4 + 5 = 15 cm.
- Two right triangles with sides 4 cm and 5 cm.
For a rectangle, the area is given by the multiplication of the dimensions, hence:
Ar = 8 x 15 = 120 cm²
For each right triangle, the area is given by half the multiplication of the sides, hence:
At = 2 x 0.5 x 4 x 5 = 20 cm².
Then the surface area of the prism is:
S = 120 cm² + 20 cm² = 140 cm².
More can be learned about surface area at brainly.com/question/28123954
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28/7=4km is car journey covered by car in 1l
64/4=16l
I think I know what it forms - a cone!!
I'm guessing that the angles at the end are 10 degrees so that would make angle CAB equal 5 degrees.
Line AB would be the radius of the "upper cone".
Line BC is 12/2 or 6
tangent (A) = BC / AB
tangent (5) = 6 / AB
AB = 6 / tan(5)
AB = 6 / 0.087489
AB =
<span>
<span>
<span>
68.58 which is the radius of the "upper cone".</span></span></span>
Cone Volume = (PI * radius^2 * height) / 3
Cone Volume = (PI * 68.58 * 68.58 * 6) / 3
Cone Volume =
<span>
<span>
<span>
29,551
That is just the "upper cone volume. So, we multiply </span></span></span><span><span>
<span>
<span>
29,551 * 2
and get 59,102 which is the volume of the entire solid.
</span></span></span> </span>
Source for cone volume:
http://www.1728.org/volcone.htm