17-7 (x-3) + x = 86 equations w/ distributing and variables on both sides

Asystem of equation is shown below 6x - 2y equals 3 . and 5x + 3y equals 4. would you solve by substitution or elimination? and why

Mrs. avila is buying a wallpaper border to go on all of her kitchen walls. she wants to buy 5 extra feet of wallpaper border than she needs to be sure she has enough. she buys 55.5 feet of the border. the store owner selling the border uses the width of mrs. avila's kitchen to determine that the length of her kitchen must be 14.5 feet.

Which of the following circles have their centers in the third quadrant?