Linear equation - One variable. 1  A linear equation in one unknown x may always be rewritten. 2  If a â  0, there is a unique solution. 3  If a = 0, then, when b = 0 every number is a solution of the equation, but if b â  0 there are no solutions (and the equation is said to be inconsistent.)
How effective is the Depo shot? The birth control shot â Depo-Provera â is one of the most effective methods of birth control available. Each shot of Depo-Provera will protect you from pregnancy for 12 weeks. It works best when you get the birth control shot regularly, every 12 weeks. Fewer than one out of 100 women will get pregnant each year if they always use the birth control shot as directed. About six out of 100 women will get pregnant each year if they donât always use the birth control shot as directed.
Depo-Provera is a contraceptive method for women. Itâs made of a hormone similar to progesterone. It's a shot that a doctor gives you in the arm or buttocks. Each shot works for up to 12 to 14 weeks, but you must get the injection once every 12 weeks to get its full protection.epo-Provera starts to work as birth control immediately after the first shot, if you get it within the first 5 days of your menstrual period. Itâs 99% effective in preventing pregnancy.