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

$$ \begin{aligned} \left( \color{blue}{ x-10}\right) \cdot \left( \color{orangered}{ -3x+270}\right) &= \underbrace{ \color{blue}{x} \cdot \left( \color{orangered}{-3x} \right) }_{\text{FIRST}} + \underbrace{ \color{blue}{x} \cdot \color{orangered}{270} }_{\text{OUTER}} + \underbrace{ \left( \color{blue}{-10} \right) \cdot \left( \color{orangered}{-3x} \right) }_{\text{INNER}} + \underbrace{ \left( \color{blue}{-10} \right) \cdot \color{orangered}{270} }_{\text{LAST}} = \\ &= -3x^2 + 270x + 30x + \left( -2700\right) = \\ &= -3x^2 + 270x + 30x + \left( -2700\right) = \\ &= -3x^2+300x-2700; \end{aligned} $$

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