Answer:
The original inequality is 1+x < 5
That inequality solves to x < 4
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Explanation:
The term "sum" means "result of addition". For example, the sum of 3 and 7 is 3+7 = 10.
In this problem, the sum of 1 and x is 1+x. We don't know what x is, so we can't combine it with the 1. We leave it as is.
The expression 1+x is less than 5, meaning we write 1+x < 5
To solve this, we subtract 1 from both sides
1+x < 5
1+x-1 < 5-5
x < 4 is what happens when you isolate x.
This describes any number smaller than 4.
