The given equation is,
Part 1:
Solve the above equation for n.
Using distributive property of multiplication,
Now, group the like terms.
Now, add the like terms.
0=-12 is a false statement.
Since we obtained a false statement, the given equation has no solution.
So, option b is correct.
Part 2:
The option (a) is n=3.
If while solving an equation, a single value is obtained for the variable, then the equation has only a single solution. If n=3 is obtained after solving the equation, then the student should chose option (a) as the answer.
The option (b) is "no solution".
While solving an equation, if we obtain an equation which is mathematically false, then the equation will have no solution. So, no solution is chosen when no value is obtained for n and the final equation is mathematically false.
The option (c) is "infinitely many solutions".
While solving an equation, if we obtain an equation which is mathematically correct such as 0=0, 7=7 etc., then the equation will have infinietly many solutions. So, infinitely many solutions is chosen when no value is obtained for n and the final equation is mathematically correct.
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