This week we started a new chapter. Intercepts. There are two types of intercepts. The x- and y intercepts. The x intercept is the point where the line/ graph crosses the x-axis, the y intercept is the point where the line/ graph crosses the y-axis. When you have only a function given, that includes x and y, you have to insert 0 in either x or y. For example if you are locking for the x-intercept you have to insert 0 for y and then solve it like a normal equation.

e.g.: 3x + 5y = 30

x-intercept -> y = 0                      y-intercept -> x = 0

3x + 5 . (0) = 30                             3 . (0)+ 5y = 30

3x + 0 = 30                                    0 + 5y = 30

3x = 30  | :3                                   5y = 30  | :5

x = 10                                              y = 6

The number you are inserting x or y with always has to be in brackets!

–> Otherwise it can might lead to misconceptions, for example if you have a negative number that gets squared it makes a huge difference whether your number is in brackets or not. If  your number is in brackets the product will be positive, because the “-” gets squared too (“-” times “-” becomes “+”). If your number isn’t in brackets only the number without the algebraic sign gets squared and the result will be negative (“-” times “+” becomes “-“).