Completing square

Solve the quadratic equation: m²=4m+20 using completing the square method

Correct answer:

m₁ =  6.899
m₂ =  -2.899

Step-by-step explanation:

$$\begin{gathered} m^2=4m+20 \\ {m}^2-4m-20=0 \\ (m-2{)}^2-4-20=0 \\ (m-2{)}^2-24=0 \\ (m-2{)}^2=24 \\ m-2=\pm \sqrt{24} \\ {m}_1=2+\sqrt{24}=6.899 \end{gathered}$$

$m_2=2-\sqrt{24}=-2.899$

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