Questions: Factor the following trinomial: y^2 - 7y - 18
Transcript text: Question
Factor the following trinomial: $y^{2}-7 y-18$
Provide your answer below:
Solution
Solution Steps
To factor the trinomial \( y^2 - 7y - 18 \), we need to find two numbers that multiply to the constant term (-18) and add up to the coefficient of the linear term (-7). Once we find these numbers, we can rewrite the middle term and factor by grouping.
Step 1: Identify the Trinomial
We start with the trinomial:
\[ y^2 - 7y - 18 \]
Step 2: Find Two Numbers
We need to find two numbers that multiply to \(-18\) (the constant term) and add up to \(-7\) (the coefficient of the linear term).
Step 3: Factor the Trinomial
The two numbers that satisfy these conditions are \(-9\) and \(2\). Therefore, we can rewrite the trinomial as:
\[ y^2 - 9y + 2y - 18 \]
Step 4: Group and Factor by Grouping
Group the terms to factor by grouping:
\[ (y^2 - 9y) + (2y - 18) \]
Factor out the common factors in each group:
\[ y(y - 9) + 2(y - 9) \]
Step 5: Factor Out the Common Binomial
Factor out the common binomial \((y - 9)\):
\[ (y - 9)(y + 2) \]
Final Answer
The factored form of the trinomial \( y^2 - 7y - 18 \) is:
\[ \boxed{(y - 9)(y + 2)} \]