Answer:
<em>A.</em>
<em>The student made an error in step 3 because a is positive in Quadrant IV; therefore, </em>
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Step-by-step explanation:
Given



Required
Where and which error did the student make
Given that the angle is in the 4th quadrant;
The value of r is positive, a is positive but b is negative;
Hence;

Since a belongs to the x axis and b belongs to the y axis;
is calculated as thus

Substitute 


Rationalize the denominator


So, from the list of given options;
<em>The student's mistake is that a is positive in quadrant iv and his error is in step 3</em>
Answer:
9
Step-by-step explanation:
2/5 x 2 = 4/5
4/5 x 2, or 2/5 x 4 = 1 3/5
1 3/5 x 2, or 2/5 x 8 = 3 1/5
3 1/5 + 2/5, or 2/5 x 9 = 3 3/5
It's 627,751. You're welcome.
Answer: 
<u>Step-by-step explanation:</u>

NOTE: The sign between 4x and 7 is missing in the question you posted. I assumed it was 4x + 7 in order to solve the equation.
i’m not from kentucky but it’s A
lmk if you need me to explain