Answer:
15
Step-by-step explanation:
Jackie would've washed 15 cars, since multiplying 2 x 5 = 10, so you'd have to multiply 3 by 5 to get the amount of cars Jackie washed if Michael washed 10.
The 'i' should go in front of the square root, not inside it.
So the answer should be 
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The way they wrote the expression
is bit misleading as it might imply that the 'i' is under the square root. However the square root ends after the "5". It might be better to say
so there is clearer separation. But sticking the "i" in front is also a valid option.
side note: the plus minus part is already handled so there's no need to worry about that.
Answer:
The answer is a and d
Step-by-step explanation:
First bring like terms together before simplifying
If i did the math right it would be (C)