A) -3 · x = -21

b) -7x + 16 = 2x - 20

Step-by-step explanation:

a) -3x = -21

Divide both sides by (-3)

-3x/-3 = -21/-3

x = 7

b)  -7x + 16 = 2x - 20

Subtract 16 from both sides

-7x + 16 -16 = 2x - 20 -16

-7x = 2x - 36

Subtract 2x from both sides

-7x -2x = 2x - 36 - 2x

-9x = -36

Divide both sides by (-9)

-9x/-9 = -36/-9

x = 4

blue marble is 15 times out of 50 = 15/50 reduces to 3/10

landing on tails is 24 out of 50 = 24/50 reduces to 12/25

to find the probability of both multiply together:

3/10 x 12/25 = 3 x 12 / 10 x 25 = 36/250

if you multiplied the numerator and denominator by 10 you get 360/2500.

the answer is 360/2500

answer: haha (: i’ll go see what it is

step-by-step explanation: