Question

Difficulty: EasySolving Quadratic Equations by Factoring

The quadratic equation x24x12=0x^2 - 4x - 12 = 0 has two real solutions. What is the value of the positive solution to this equation?

Answer: 6

Answer

The positive solution to the equation is 66.
Factoring the quadratic trinomial x24x12=0x^2 - 4x - 12 = 0 yields (x6)(x+2)=0(x - 6)(x + 2) = 0. Setting the individual binomial factors to zero gives the solutions x=6x = 6 and x=2x = -2. The positive solution among these is 66.

Step-by-Step Solution

1
Factor the quadratic equation
(x6)(x+2)=0(x - 6)(x + 2) = 0
Factoring the trinomial x24x12x^2 - 4x - 12 requires finding two integers whose product is 12-12 and whose sum is 4-4. These numbers are 6-6 and 22.
2
Apply the zero product property
x6=0x - 6 = 0 or x+2=0x + 2 = 0
If the product of two factors is equal to zero, then at least one of the individual factors must equal zero.
3
Solve for the variable and identify the positive root
x=6x = 6 and x=2x = -2
Solving the linear equations yields x=6x = 6 and x=2x = -2. Since the question asks for the positive solution, we select 66.

Key Concept

Solving quadratic equations by factoring
Rate this question