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3 years ago

Wat is 7x² + 4x - 5= 0

Mathematics

2 answers:

lara [203]3 years ago

5 0

$7x^2+4x-5=0\\
\Delta=4^2-4\cdot7\cdot(-5)=16+140=156\\
\sqrt{\Delta}=\sqrt{156}=2\sqrt{39}\\
x=\dfrac{-4\pm2\sqrt{39}}{2\cdot7}=\dfrac{-2\pm\sqrt{39}}{7}$

frosja888 [35]3 years ago

4 0

Answer and workings in the attachment below.

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