The answer is: [A]: He did not apply the distributive property correctly for 4(1 + 3i) .
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Explanation:
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Note the distributive property of multiplication:
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a*(b+c) = ab + ac.
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As such: 4*(1 + 3i) = (4*1) + (4*3i) = 4 + 12i ;
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Instead, Donte somehow incorrectly calculated:
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4*(1 + 3i) = (4*1) + 3i = 4 + 31; (and did the rest of the problem correctly);
Note: - (8 - 5i) = -8 + 5i (done correctly;
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So if Donte did not apply the distributive property correctly for 4*(1+3i)—and incorrect got 4 + 3i (as mentioned above); but did the rest of the problem correctly, he would have got:
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4+ 3i - 8 + 5i = -4 + 8i (the incorrect answer as stated in our original problem.
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This corresponds to: "Answer choice: [A]: <span>He did not apply the distributive property correctly for 4(1 + 3i)."
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Answer:
Volume of a sphere = 4πr³/3
r=10
V = 4πx10³/3
=4000π/3
V= 1333.33π (in terms of pi)
or
V= 4188.79(Nearest Hundredth).
Answer:
The dimension of the cardboard is 34 cm by 34 cm by 17 cm.
Step-by-step explanation:
Let the dimension of the cardboard box be x cm by y cm by z cm.
The surface area of the cardboard box without lid is
f(x,y,z)= xy+2xz+2yz.....(1)
Given that the volume of the cardboard is 19,652 cm³.
Therefore xyz =19,652
......(2)
putting the value of z in the equation (1)
The partial derivatives are
To find the dimension of the box set the partial derivatives 
and 
.Therefore 
.......(3)
and 
.......(4)
Now putting the x in equation (3)
⇒y=34 cm
Then 
=34 cm.
Putting the value of x and y in the equation (2)
=17 cm.
The dimension of the cardboard is 34 cm by 34 cm by 17 cm.
