How do you solve ( x + 5) > 91?

1 Answer
Oct 6, 2017

x>86

Explanation:

To solve inequalities, initially pretend that the > sign is actually an = sign. Once you to that, you end up with:

x+5 = 91

Subtract 5 from both sides to isolate x and you get:

x = 86

Now that you've solved for x, you should replace the > sign.

BE CAREFUL because if you multiply or divide an inequality by a negative number, you need to reverse the inequality sign.

In your case, you didn't multiply or divide by a negative, so replace the = with >, and you end up with:

x > 86

To check this, you can plot it and see if the domain makes sense.

Looking at the original equation, you know you need a high, positive number as x in order to be more than 91. Your number line should start far right and continue to the right forever.