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Can you guys please help me solve these

Can you guys please help me solve these-example-1

1 Answer

7 votes

Answer:

See explanation below

Explanation:

In all cases you need to isolate x on one side of the inequality symbol using inverse operations.

1.-


15+x\leq -45\\15-15+x\leq -45-15\\x\leq -60

where we subtracted from both side 15 in order to leave x by itself on the left.

2.-


x-14>12\\x-14+14>12+14\\x>26

where we added 14 in order to isolate x on the left

3.-

In this case we need to divide both sides by -5 in order to isolate the x which is being multiplied by the factor -5, but he have to recall that multiplying or dividing by a negative number changes the direction of the inequality symbol (in our case from < into > )


-5x<35\\(-5\,x)/(-5) >(35)/(-5) \\x>-7

4.-


2x>-42\\(2\,x)/(2) >(-42)/(2) \\x>-21

In this case we simply divide both sides by two, and there is no change in the direction of the inequality because the number we are using to divide is a positive number (2)

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