Question
Solve the following quadratic equations by factorisation : 3y² = 15 y
✓
Answer
$\begin{array}{l}
3 y^2=15 y \\
\therefore 3 y^2-15 y=0 \\
\therefore 3 y(y-5)=0 \\
\therefore 3 y=0 \text { or }(y-5)=0 \\
\therefore y=0 \text { or } y=5
\end{array}$
$\therefore 0$ and $5$ are the roots of quadratic equation.
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