Which of the following the best describe a valence electron

Can some one me with these questions

20 solve 2(4 x + 3) < 5 x + 21. a) { x | x < 9} b) { x | x > -5} c) { x | x > -9} d) { x | x < 5}

The first side of a triangle measures 5 in less than the second side, the third side is 3 in more than the first side, and the perimeter is 17 in. how long is the third side? if s represents the length of the second side, which of the following represents the length of the third side? s-5 ws-2 s+ 3 next question ask for turn it in