Solution - Linear inequalities with one unknown
Step-by-step explanation
1. Simplify the expression
Expand the parentheses:
Multiply the coefficients:
Simplify the arithmetic:
2. Group all constants on the right side of the inequality
Subtract from both sides:
Simplify the arithmetic:
Simplify the arithmetic:
3. Isolate the x
Divide both sides by -6:
Whenever you multiply or divide by a negative, reverse the inequality sign:
Cancel out the negatives:
Simplify the fraction:
Move the negative sign from the denominator to the numerator:
Simplify the fraction:
4. Plot the solution on a coordinate grid
Solution:
Interval notation:
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Please leave us feedback.Why learn this
Inequalities help us understand how systems work by setting boundaries. For example, a speed limit of 30 miles per hour does not mean we have to drive exactly 30 miles per hour and, instead, establishes a boundary for what is allowable — drive more than 30 miles per hour and risk getting a ticket. This could be modelled mathematically as .
There are also situations where there is more than one boundary. In our speed limit example, there may also be a lower speed limit of 15 miles per hour to prevent drivers from driving too slowly. The two boundaries together could be modelled mathematically as , in which represents all of the possible values between or equal to 15 and/or 30.
Furthermore, anytime we say something along the lines of, "it will take at least twenty minutes to get there," or "the car can hold five people at most," we are expressing the numerical boundaries of something and, therefore, speaking in terms of inequalities.