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2x+1<7 solve and show the solution of the inequality on a number line​

User Amod
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1 Answer

6 votes

Answer:

x<3 number line: < ---------------3 - - - - - > (open circle/parentheses on 3)

Explanation:

first, solve for x:

2x+1<7 <-- treat the less than sign as an equal sign

2x+1=7 <-- get x by itself on the left hand side by subtracting 1 from both sides

-1 -1

2x=6 <--- divide both sides by 2 to get x by itself

2x/2 = x 6/2 = 3

x=3 < -- substitute the less than symbol back into the equation to get x<3

to plot on a number line:

x is less than 3, so on the number line, any real numbers to the left of three will be true for this equation

< ---------------3 - - - - - >

since 3 is not included in the answer, there would be an open circle or a parentheses where 3 is.

we know 3 is not included in the answer because of the inequality sign. if the inequality symbol is ≥ or ≤, then the answer on the number line would be a closed circle or a bracket.

in interval notation, the answer would be (-∞,3)

User Colin Humber
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