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3 years ago

Solve for x. 7 – 4x = 31 A. x = 6 B. x = 9.5 C. x = –6 D. x = –9.5

Mathematics

2 answers:

Eduardwww [97]3 years ago

5 0

7-4x= 31

Bring over 7 to the other side

Positive 7 changes into negative 7

7-7-4x= 31-7

-4x= 24

Divide by -4 for -4x and 24

-4x/-4= 24/-4

x= -6

Check answer by using substitution method

7-4x= 31

7-4(-6)= 31

7+24= 31

31= 31

Answer : C. x= -6

Bingel [31]3 years ago

4 0

Answer:

C. x = -6

Step-by-step explanation:

Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.

First, subtract 7 from both sides:

7 - 4x = 31

7 (-7) - 4x = 31 (-7)

-4x = 31 - 7

-4x = 24

Divide -4 from both sides to isolate the variable, x:

(-4x)/-4 = (24)/-4

x = 24/-4

x = -6

x = -6, or C. is your answer.

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3 years ago

Washing his dad's car alone, eight-year-old Levi takes 2.5 hours. If his dad helps him, then it takes 1 hour. How long does it t

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Answer:

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Step-by-step explanation:

* Lets explain how to solve the problem

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Read 2 more answers

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