Answer:

Step-by-step explanation:
we know that
The volume of a trough is equal to

where
B is the area of equilateral triangle
L is the length of a trough
step 1
Find the area of equilateral triangle B
The area of a equilateral triangle applying the law of sines is equal to

where


substitute


step 2
Find the volume of a trough

we have


substitute


Answer:
∠B = 41°
Step-by-step explanation:
∠BCD is an exterior angle of the triangle
The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠A and ∠ B are the 2 opposite interior angles, hence
∠A + ∠B = 113, that is
72 + ∠B = 113 ( subtract 72 from both sides )
∠B = 41°
Answer:
The answer is yes most shapes do have line of symmetry for such task. The ones that don't would be irregular shapes or small changes to its handle on more obscure symmetrical shapes, ie) they do not fit in itself due to a handle being rotated before hand, so things that appear to be symmetrical can have a symmetrical line even if they do not fit in their selves at say anything under 360 rotation.
Step-by-step explanation:
9514 1404 393
Answer:
B) 171 units^2
Step-by-step explanation:
The area is given by the formula ...
A = 1/2(b1 +b2)h
Filling in the given base and height values, we find the area to be ...
A = 1/2(23 +15)(9) = (19)(9) = 171 . . . square units
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<em>Additional comment</em>
You can select the correct answer choice simply on the basis of "reasonableness." If this were a 9×15 rectangle, its area would be 9×15 = 135 square units, more than 85.5. You know its area is less than a 9×23 rectangle, so is less than 9×23 = 207 square units. Only one answer choice is a value between 135 and 207.
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Multiplication by 9 is not so hard. It is multiplication by 10-1:
15×9 = 15×(10 -1) = 150 -15 = 135
67

Multiply the denominator to the whole number. 4*67=268. Now add the numberator. 268 + 3 is 271. Your answer is