# x² - 5x = 18 + 2x

Question
$$\displaystyle{x}²-{5}{x}={18}+{2}{x}$$

2021-01-07
We are given: $$\displaystyle{x}²-{5}{x}={18}+{2}{x}$$
Write in the form $$\displaystyle{a}{x}²+{b}{x}+{c}={0}$$
$$\displaystyle{x}²-{7}{x}-{18}={0}$$
Factor the left side: (x+2)(x-9)=0
By zero product property, x+2=0 and x-9=0
x=-2 and x=9

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