Question

Solve the following quadratic equation by factorisation.

7m² = 21m

Answer 1

\[7 m^2 = 21m\] 

\[\Rightarrow 7 m^2 - 21m = 0\]
\[ \Rightarrow 7m\left( m - 3 \right) = 0\]
\[ \Rightarrow 7m = 0 \text{ or } m - 3 = 0\]
\[ \Rightarrow m = 0 \text{ or } m = 3\]