To express \((3x+1)(x-4)\) as a trinomial, you can use the distributive property (also known as the FOIL method for binomials).
- First: Multiply the first terms: \(3x \cdot x = 3x^2\)
- Outer: Multiply the outer terms: \(3x \cdot (-4) = -12x\)
- Inner: Multiply the inner terms: \(1 \cdot x = 1x\)
- Last: Multiply the last terms: \(1 \cdot (-4) = -4\)
Now, combine all these results:
\[ 3x^2 - 12x + 1x - 4 \]
Combine the like terms \(-12x\) and \(1x\):
\[ 3x^2 - 11x - 4 \]
So, the expression \((3x + 1)(x - 4)\) as a trinomial is:
\[ 3x^2 - 11x - 4 \]