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Solve for x ! problems attached please help!!

Solve for x ! problems attached please help!!-example-1
User Manicaesar
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2 Answers

6 votes
I answered all questions in the attached image. Remember that solving inequalities is very similar to solving equations. Just remember to change the sign when you divide by a negative number.
Also, when dealing with compound inequalities, you need to split them up and solve for x. This is demonstrated in the attached image.
Solve for x ! problems attached please help!!-example-1
User Rodrigo Curbelo
by
8.8k points
4 votes

Answer:

7.
x\le 8

8.
x\le 1.7

9.
-0.2\le x\le 2

10.
3< x\le 4

Explanation:

7. Solve for x:


4x+7-x\le 31

Separate variable and numbers into different sides of inequality:


4x-x\le 31-7\\ \\3x\le 24

Divide the inequality by 3:


x\le 8

8. Solve for x:


2(x-3)+8x\le 11

Eliminate the brackets:


2x-6+8x\le 11

Separate variable and numbers into different sides of inequality:


2x+8x\le 11+6\\ \\10x\le 17

Divide the inequality by 10:


x\le 1.7

9. Solve for x:


-7x\le 3x+2\le 8

Solve two inequalities
-7x\le 3x+2 and
3x+2\le 8 separately:


-7x\le 3x+2\\ \\3x+2\ge -7x\\ \\3x+7x\ge -2\\ \\10x\ge -2\\ \\x\ge -0.2

and


3x+2\le 8\\ \\3x\le 8-2\\ \\3x\le 6\\ \\x\le 2

So,


-0.2\le x\le 2

10. Solve for x:


8<3x-1\le 11

Add 1:


8+1<3x\le 11+1\\ \\9<3x\le 12

Divide by 3:


3< x\le 4

User Donentolon
by
7.9k points