In this example we are multiplying two binomials so FOIL method can be used.

$$ \begin{aligned} \left( \color{blue}{ 2x-6}\right) \cdot \left( \color{orangered}{ 3x+7}\right) &= \underbrace{ \color{blue}{2x} \cdot \color{orangered}{3x} }_{\text{FIRST}} + \underbrace{ \color{blue}{2x} \cdot \color{orangered}{7} }_{\text{OUTER}} + \underbrace{ \left( \color{blue}{-6} \right) \cdot \color{orangered}{3x} }_{\text{INNER}} + \underbrace{ \left( \color{blue}{-6} \right) \cdot \color{orangered}{7} }_{\text{LAST}} = \\ &= 6x^2 + 14x + \left( -18x\right) + \left( -42\right) = \\ &= 6x^2 + 14x + \left( -18x\right) + \left( -42\right) = \\ &= 6x^2-4x-42; \end{aligned} $$

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