Answer
\[\left( 2x-5 \right)\left( 3x+4 \right)=6{{x}^{2}}-7x-20\].
Work Step by Step
Consider,
\[\begin{align}
& \left( 2x-5 \right)\left( 3x+4 \right)=\underbrace{2x\cdot 3x}_{\text{F}}+2\underbrace{x\cdot 4}_{\text{O}}+\underbrace{\left( -5 \right)\cdot 3x}_{\text{I}}+\underbrace{\left( -5 \right)\cdot 4}_{\text{L}} \\
& =6{{x}^{2}}+8x-15x-20 \\
& =6{{x}^{2}}-7x-20
\end{align}\]
Where, “F” stands for the product of the first term, “O” stands for the product of the outside terms, “I” stands for the product of the inside term, and “L” stands for the product of the last term.
Thus \[\left( 2x-5 \right)\left( 3x+4 \right)=6{{x}^{2}}-7x-20\].
