Need help with an algebra 2 problem

you want to install 3 ceiling lights in a row in your garage. each light = 3 ft long, garage = 27 ft long. distance between each light should be about the same. also the distance between the lights and the walls should be half the distance between any 2 consecutive lights. what is the distance between successive lights? show all work

3 lights at 3 feet each is a total of 9 feet.

There will be a total of 2 spaces in between lights... each with a distance of X in between... 2 * X = 2X
There will be a total of 2 spaces in between lights and walls with a distance of .5X in between... 2 * .5X = X

Your equation is:

2X + X + 9 = 27
3X + 9 = 27
3X = 18
X = 6

There should be 6 feet in between lights and 3 feet between lights and walls.

So, if we say L is the length of a light, and S is the space between each light:

27 = .5S + L + S + L + S + L + .5S

Solve for S, knowing that L = 3.

draw it out, the space between the wall and the lights is 3 feet, the space between one light and another light is 6 feet ... so your answer is 6.