Answer:

Step-by-step explanation:
A fraction can be found be taking the current amount over the total amount:

Since Darlene has only typed 23 pages out of 59, her fraction is 23 over 59. Fractions must always be in simplest form, which means that both the numerator and denominator can no longer be divided by the same factor. Since the numbers 23 and 59 are both prime and have no other factors other than 1 and themselves, the fraction 23/59 is in simplest form.
Answer:

Step-by-step explanation:
How do we find the line that's perpendicular to another?
We find the negative reciprocal. So for example if our slope is 2, the negative reciprocal would be
.
Answer:
a/9 - 4
Step-by-step explanation:
set up a ratio to find the length:
15/12 = DE/16
cross multiply the 15 & 16:
15 * 16 = 240
divide that by 12 to get DE
240 / 12 = 20
DE = 20