Question

Write the quadratic equation whose roots are 3 and -5, and whose leading coefficient is 2.

Answer 1

$\begin{cases} x=3\implies &x-3=0\\ x=-5\implies &x+5=0 \end{cases}\qquad \implies\qquad a(x-3)(x+5)=\stackrel{0}{y} \\\\\\ a(\stackrel{F~O~I~L}{x^2+2x-15})=y\implies \stackrel{\textit{leading coefficient of 2}}{2(x^2+2x-15)}=y\implies 2x^2+4x-30=y$

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