Westonci.ca connects you with experts who provide insightful answers to your questions. Join us today and start learning! Get immediate and reliable answers to your questions from a community of experienced professionals on our platform. Connect with a community of professionals ready to provide precise solutions to your questions quickly and accurately.
Sagot :
[tex]f(x)=-9x^2+4x+9\\\\a=-9;\ b=4;\ c=9\\\\\Delta=b^2-4ac\to\Delta=4^2-4(-9)(9)=16+324=340\\\\x=\frac{-b\pm\sqrt\Delta}{2a}\\\\\sqrt\Delta=\sqrt{340}=\sqrt{4\times85}=2\sqrt{85}\\\\x=\frac{-4\pm2\sqrt{85}}{2(-9)}=\frac{2\pm\sqrt{85}}{9}\\\\x_1\approx1.25\ and\ x_2\approx0.8[/tex]
[tex]f(x) = -9x^2 + 4x + 9\ \ \ and\ \ \ f(x)=0\\\\-9x^2 + 4x + 9=0\ \ \ \Leftrightarrow\ \ \ 9x^2 - 4x + \frac{4}{9} -\frac{4}{9}- 9=0\\\\(3x-\frac{2}{3})^2=9\frac{4}{9}\ \ \ \Leftrightarrow\ \ \ (3x-\frac{2}{3})^2= \frac{85}{9} \\\\3x-\frac{2}{3}= \frac{ \sqrt{85} }{3} \ \ \ or\ \ \ \ \ \ 3x-\frac{2}{3}= -\frac{ \sqrt{85} }{3}\\\\3x= \frac{2+ \sqrt{85} }{3} \ \ \ \ \ \ or\ \ \ \ \ \ 3x= \frac{2- \sqrt{85} }{3}\\\\ x= \frac{2+ \sqrt{85} }{9} \ \ \ \ \ \ \ \ or\ \ \ \ \ \ \ x= \frac{2- \sqrt{85} }{9}\\\\[/tex]
[tex]x\approx1.247\ \ \ \ \ \ \ \ or\ \ \ \ \ \ \ x\approx-0.802[/tex]
[tex]x\approx1.247\ \ \ \ \ \ \ \ or\ \ \ \ \ \ \ x\approx-0.802[/tex]
We appreciate your visit. Our platform is always here to offer accurate and reliable answers. Return anytime. We hope you found this helpful. Feel free to come back anytime for more accurate answers and updated information. Thank you for trusting Westonci.ca. Don't forget to revisit us for more accurate and insightful answers.