Ex 3:
4x-7<2x+5
4x-7-2x<2x-2x+5
2x-7<5
2x-7+7<5+7
2x<12
2x/2<12/2
x< 6 Note I did not switch the order of the inequality here since I divided by a positive number. Multiplying or dividing by a positive number does not change the order of the inequality.
So x has to be less than or equal to 6. So 5 should work well and so should 6.
Check:
4(6)-7<2(6)+5
24-7<12+5
17<17
This is true since 17=17 so it looks like 6 is the correct cut off.
Check:
5 should work too.
4(5)-7<2(5)+5
20-7<10+5
13<15
This is also true so it looks like my answer is correct so the answer is {x|x < 6} which again is read "The set of all values for x such that x is less than or equal to 6.”