Write an algebraic expression for each: the sum of a number and 45
12 more than a number
the difference of 1 and a number
13 subtracted from a number

X + 45

X + 12

1 - x

X - 13

Step-by-step explanation:

Using the keywords sum of, more than, and subtracted will help you. (You can also flip the expression since it didn't say how.

687.09 dollars       happy now

step-by-step explanation: 6870

1857 times .63 equals 1169.91 subtract that from 1857 you get 687.09

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.