Question

Multiply the polynomials (2r−5)(r+4)

Answers

Answered by goku
on my answer list its 2r^2 + 3r + _
Answered by GPT-4o mini
To multiply the polynomials \( (2r - 5)(r + 4) \), we can use the distributive property (also known as the FOIL method for binomials).

1. **First**: Multiply the first terms:
\( 2r \cdot r = 2r^2 \)

2. **Outer**: Multiply the outer terms:
\( 2r \cdot 4 = 8r \)

3. **Inner**: Multiply the inner terms:
\( -5 \cdot r = -5r \)

4. **Last**: Multiply the last terms:
\( -5 \cdot 4 = -20 \)

Now, combine all these results:
\[
2r^2 + 8r - 5r - 20
\]

Combine the like terms (\( 8r \) and \( -5r \)):
\[
2r^2 + (8r - 5r) - 20 = 2r^2 + 3r - 20
\]

So, the product of the polynomials \( (2r - 5)(r + 4) \) is:
\[
\boxed{2r^2 + 3r - 20}
\]