Quadratic Equation : Roots of equation

You could expect to get a question from quadratic equation in the TANCET test.

A quadratic equation is an equation of the form ax² + bx + c = 0.

Each quadratic equation has 2 roots. The roots of the quadratic equation can be found out either by factorizing the equation or by using a formula.

If r₁ and r₂ are the roots of the quadratic equation, then
r₁ = (-b + root(b² - 4ac))/2a
r₂ = (-b - root(b² - 4ac))/2a

Here is a typical question in quadratic equation
Question
If 8 and 6 are the roots of a quadratic equation, then the equation is
(1) x² + 14x + 48 = 0
(2) x² - 14x + 48 = 0
(3) x² + 14x - 48 = 0
(4) x² - 14x - 48 = 0
(5) x² + 48x + 14 = 0

If we are given the roots of a quadratic equation, i.e., r₁ and r₂, then the quadratic equation is (x - r₁)(x - r₂) = 0.
We know that the roots of equation are 8 and 6.
Hence, the equation is (x - 8)(x - 6) = 0
or x² - 14x + 48 = 0