So here's the question.

20-7x= 6x-6

 

On khan academy, the tutor said that you should subtract 20. But aren't you sopposed to add 7x first??
in Algebra 2 Answers by

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.

1 Answer

20-7x=6x-6

Method 1

Add -20 to both sides

20-7x-20=6x-6-20

-7x=6x-26

Add -6x to both sides

-7x-6x=6x-26-6x

-13x=-26

Divide both sides by -13

-13x/-13=-26/-13

x=2

Method 2

20-7x=6x-6

20-7x+7x=6x-6+7x

20=13x-6

20+6=13x-6+6

26=13x

13x=26

13x/13=26/13

x=2

The answer will be the same. Do you see how it works?

 

by Level 7 User (29.0k points)

Related questions

1 answer
Welcome to MathHomeworkAnswers.org, where students, teachers and math enthusiasts can ask and answer any math question. Get help and answers to any math problem including algebra, trigonometry, geometry, calculus, trigonometry, fractions, solving expression, simplifying expressions and more. Get answers to math questions. Help is always 100% free!
85,994 questions
91,896 answers
2,229 comments
23,903 users