Solve for x
12x + 7x = 5x - 42

x = - 3

Step-by-step explanation:

Given

12x + 7x = 5x - 42, that is

19x = 5x - 42 ( subtract 5x from both sides )

14x = - 42 ( divide both sides by 14 )

x = - 3

X= -21/2, Please vote Brainliest.

Step-by-step explanation:

9x=5x-42

9x-5x=5x-42-5x

4x=-42

4x/4= -42/4

X= -21/2

  about 5.6 days

step-by-step explanation:

we can fill the given information into the decay equation and solve for the value of t at which half the sample remains.

the half-life is about 5.6 days.

15%

step-by-step explanation:

use the table and count the number of guesses that has two correct answers.

the following are two correct answers

10010, 01100, 11000

a total of 3 numbers having 2 correct guesses out of 20 questions.

probability of getting 2 correct guesses = the number of questions getting 2 correct answers / total number of questions.

= 3/20

to convert it into percent multiply by 100, we get

= 3/20 * 100

= 15%

the answer is 15%

you.