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3 years ago

How to solve 2x²-8x-90=0

Mathematics

1 answer:

8090 [49]3 years ago

4 0

А=2
b=-8
c=-90
D=b^2-4ac
D=64+720
D=784=28^2
X1,2=(-b-+D):2a
Х1,2=(8+-28):4
Х1=-5
Х2=9

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