mathinequalities
posted by Paige on .
I really don't understand this stuff for example: 9b3b+34<2b10
and
7a+3=24
letters represent variables so they can be anything really. Once you understand this step then the rest of the problem can start to make sense. Inequalities tell you whether something is greater/lessthan/equal. So lets say with 7a+3=24 both sides must be equal. So lets simplify by subtracting 3 from both sides. Which would get us 7a=21. We can then divide both by 7, and get a=3. To check if our answer is right we plug in 3 for a in the original equation 7(3)+3=24, which makes 21+3=24, which is finally 24=24, both sides are equal. If this is your first time using inequalities a good lesson to learn is that because both sides are equal then anything we do to one side we have to do to the other.(like when I subtracted 3). Now the other example the first step we should take is to simplify it. If we have 9b3b we can change that to 6b. so we will get 6b+34<2b10. We can work this out the same way, if we subtract 34 from both sides we get 6b<2b44. We then subtract 2b and get 4b<44, then finally we can divide by 4 to make it look nicer, b<11. A good way to remember what the "<", I use the alligator eats the bigger number, so 3<4 , you can imagine the jaws lol.(Three is greater than four). Another important thing about inequalities is when you divide or multiply by a negative you change the sign so x>3 divided by 1, would give you x<3

5,0000mkh2<57+98x