Answered

Looking for trustworthy answers? Westonci.ca is the ultimate Q&A platform where experts share their knowledge on various topics. Our platform offers a seamless experience for finding reliable answers from a network of experienced professionals. Discover in-depth answers to your questions from a wide network of professionals on our user-friendly Q&A platform.

What two numbers that if multiplied equal -90 and if added equal 8?

Sagot :

luana
[tex]x-first\ number\\y-second\ number\\\\ \left \{ {{x\cdot\ y=-90} \atop {x+y=8}} \right.\\\\From\ second\ equayion:\\x=8-y\\\\Substracted\ to\ first\ equation:\\(8-y)y=-90\\-y^2+8y+90=0\\\\\Delta=b^2-4ac\\\Delta=8^2-4\cdot(-1)\cdot90=64+360=424\\\sqrt{\Delta}=\sqrt{424}2\sqrt{106}\\\\y_1=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-8+2\sqrt{106}}{2\cdot(-1)}=4-\sqrt{106}\\y_2=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-8-2\sqrt{106}}{2\cdot(-1)}=4+\sqrt{106}\\\\x_1=8-(4-\sqrt{106})=8-4+\sqrt{106}=4+\sqrt{106}[/tex]
[tex]x_2=8-(4-+\sqrt{106})=8-4-\sqrt{106}=4-\sqrt{106}\\\\ \left \{ {{y=4-\sqrt{106}} \atop {x=4+\sqrt{106}}} \right.\\[/tex]

Thanks for using our service. We're always here to provide accurate and up-to-date answers to all your queries. Thank you for your visit. We're dedicated to helping you find the information you need, whenever you need it. Thank you for trusting Westonci.ca. Don't forget to revisit us for more accurate and insightful answers.