The numerical difference of the roots of x² -7x -9=0 is
Answers
Step-by-step explanation:
A quadratic equation is a special equation, usually in the form ax² + bx + c = 0, where x is an unknown, a is some number other than zero, and b and c can be any numbers. The graph of this equation is always a parabola (sort of like a soup bowl, either right-side-up or upside-down), which may or may not cross the x axis.
Say you have the equation x² - 4 = 0. The steps are simple.
1. Write two sets of parentheses.
( ) ( )
2. In the first set, write the square root of the x² term (just x), a '+' sign, then the square root of the second term, 4. You should therefore get :
(x + 2)
3. In the second set, write the two squares again, but this time put a '-' between them.
(x - 2)
4. Either of the factors may be 0, so set up each factor as an expression equal to 0.
(x + 2) = 0; (x - 2) = 0
5. If x + 2 = 0, then subtracting 2 from both sides results in:
x = -2.
6. If x - 2 = 0, then adding 2 to both sides results in:
x = 2.
7. The variable x may be 2 or -2.