Simplify the following expression:
3x (7x-4)-(x-8)

=21x2−13x+8

Step-by-step explanation:

=3x(7x−4)+−1(x−8)

=3x(7x−4)+−1x+(−1)(−8)

=3x(7x−4)+−x+8

Distribute:

=(3x)(7x)+(3x)(−4)+−x+8

=21x2+−12x+−x+8

Combine Like Terms:

=21x2+−12x+−x+8

=(21x2)+(−12x+−x)+(8)

=21x2+−13x+8

1 3 5

step-by-step explanation:

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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.