179k views
5 votes
-3x-8>19?I have to solve for x



2 Answers

10 votes

Answer:


\huge \: x < - 9


\huge \: x \in (-∞,-9)

Explanation:

to understand this

you need to know about:

  • inequality
  • PEMDAS

given:


  • -3x-8>19

tips and formulas:

the direction of inequality doesn't change when you

  • Add (or subtract) a number from both sides
  • Multiply (or divide) both sides by a positive number
  • Simplify a side

the direction of inequality does change when you

  • Multiply (or divide) both sides by a negative number
  • Swapping left and right hand sides

let's solve:


step - 1 : define \\ -3x-8>19


step - 2 : \\ add \: 8 \: to \: both \: sides


-3x-8 + 8>19 + 8


- 3x >27


step - 3 \: \\ divide \: both \: sides \: by \: - 3 \: and \: swap \: the \: inequality


\huge \therefore \: x < - 9

User Rosauro
by
4.7k points
8 votes

Answer:

x < -9

Explanation:

Add 8 to both sides:

-3x - 8 > 19

-3x > 27

Divide each side by -3:

-3x > 27

Dividing by a negative number on each side switches the inequality:

x < -9

So, the answer is x < -9

User Peter Pei Guo
by
4.0k points