Okay. In my opinion, all the class has to do is simplify the expressions and compare. But they want to substitute instead.
Well then.
First, let's notice that these are linear expressions, meaning that if they are equivalent then all their values match up.
Number 1 is not a good one. Just because they're both positive doesn't mean anything; they have to be <em>the same.</em>
This also eliminates 3.
Number 2 is a good one, but it's not as reliable. If, for instance, the two expressions are <em>not </em>equivalent and you get lucky enough to pick that one value they intersect at (or have in common), then you'd be wrong when you say they are equivalent.
Number 4 makes the most sense because if both expressions are equivalent, then every value matches up. If not, then only one will. So having two values to substitute will most definitely answer the class question.
Hope this helps, let me know if I messed up! ;)
Answer:
61.538
Step-by-step explanation:
The answer is 16
Refer image for working :-
Drop comments if any doubt arises.
1/2 of 40 is 20, and the question says 1/4 of the REMAINING cookies, and 1/4 of 20 is 5. There are 3/4 left, or 15 cookies. I hope this helps!
