9514 1404 393
Answer:
17. n -16 = 29
18. the solution to the third equation is not n=13
Explanation:
17. As with many "doesn't belong" questions, you can make up a rule that will select just about any answer you want to choose. For example, the equation ...
12 +n = 25
is the only equation that has n as the second term, not the first term. It could be said not to belong on that basis.
Similarly, the fourth equation is the only one with single-digit constants, so it could be said not to belong based on that.
__
However, if we look at the solutions to these equations, we see another way to decide "doesn't belong."
- n +14 = 27 ⇒ n = 13
- 12 +n = 25 ⇒ n = 13
- n -16 = 29 ⇒ n = 45 . . . . different solution
- n -4 = 9 ⇒ n = 13
So, we can choose the third equation as "doesn't belong" on the basis of its solution being different from the others.
__
18. The reasoning is shown above. The third equation is the only one with a solution that is not n = 13.