Answer:
i think both of them cant be
The correct answer:
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Explanation:
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Assuming you mean:
" √(9a²) + (√49b) − a + √b " ;
Simplify the expression:
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Note that: " √(9a²) = 3a " ;
"√(49b) = 7√b " ;
And we write the expression
→ " 3a + 7√b − a + √b " ;
Combine the "like terms:
" + 3a − a = 2a " ;
" + 7√b + 1√b = 8√b " ;
Rewrite:
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" 2a + 8√b " ; which is: Answer choice: [C]: " 2a + 8√b " .
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Answer:
Luis:

Marina:

Answer: Marina got the better percent score than Luis
Marina:
Answer:

Step-by-step explanation:
Let h be the cylinders height and r the radius.
-The volume of a cylinder is calculated as:

-Since the cone is within the cylinder, it has the same radius as the cylinder.
-Let
be the height of the cone.
-The area of a cone is calculated as;

The volume of the solid section of the cylinder is calculated by subtracting the cone's volume from the cylinders:

Hence, the approximate area of the solid portion is 
3(4x - 4) - 7x, when simplified, is 5x - 12. So your answer would be A, or the first one.