100, because, x^2 - 20x + 100 = ( x - 10 )^2;
C. Both options A and B will allow him to meet his goal.
Looking at Drake's situation after 4 weeks, he only has $470 saved. By
his original plan, he should have had $500 saved. So he's $30 short of
his goal and has 2 weeks until his originally planned class. If he goes
with option A and takes the later class, he will save an additional $125
which is more than enough to make up the $30 short fall. So option A
will work for him to save enough money for his class. With option B, he
will save $140 for the last 2 weeks of his plan giving him a savings of
$280 for the last 2 weeks. Adding the $470 he's already saved will give
him a total savings of $470 + $280 = $750 which is enough for him to
attend his class. So option B will also allow Drake to attend his
desired class. Both options A and B allow him to meet his goal. Hence,
the answer is "c".
Answer:
15
Step-by-step explanation:

Cross multiply to get 25x = 375
Divide each side by 25 to get x = 15
Each sandwich is toasted for 2 minutes and it takes 3 seconds to flip it.
The first two sandwiches will be toasted in 2 minutes (toasting) and 6 seconds (flipping).
The two will then be switched which will take 10 seconds.
The next two will again take 2 minutes and 6 seconds.
The final sandwich will take 5 seconds to be placed.
The final sandwich will also take 2 minutes to toast and 3 seconds to flip.
Total time:
2 + 2 +2 = 6 minutes
6 + 10 + 6 + 3 = 25 seconds
Total time is 6 minutes and 25 seconds.