Questions: The difference of the square of a number and 4 is equal to 3 times that number. Find the positive solution.
Transcript text: The difference of the square of a number and 4 is equal to 3 times that number. Find the positive solution.
Solution
Solution Steps
Step 1: Formulate the Equation
We start with the statement that the difference of the square of a number and 4 is equal to 3 times that number. This can be expressed mathematically as:
\[
x^2 - 4 = 3x
\]
Step 2: Rearrange the Equation
Rearranging the equation gives us a standard polynomial form:
\[
x^2 - 3x - 4 = 0
\]
Step 3: Factor the Polynomial
Next, we factor the polynomial \(x^2 - 3x - 4\). The factorization results in:
\[
(x - 4)(x + 1) = 0
\]
Step 4: Solve for \(x\)
Setting each factor equal to zero gives us the possible solutions:
\[
x - 4 = 0 \quad \Rightarrow \quad x = 4
\]
\[
x + 1 = 0 \quad \Rightarrow \quad x = -1
\]
Step 5: Identify the Positive Solution
Among the solutions \(x = 4\) and \(x = -1\), the positive solution is:
\[
x = 4
\]