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3 years ago

Solve the equation x2 + + 7x= 30

Mathematics

1 answer:

antiseptic1488 [7]3 years ago

8 0

Answer:

x^2+7x=30

x^2+7x-30=0

Here a=1,b=7 and c=-30

Now,

Discriminant(D)=b^2-4ac

=7^2-4×1×(-30)

=49+120=169

By applying Quadratic formula

x=-b+- root over b^2-4ac÷2a

=-7+- root over D ÷ 2×1

=-7 +- root over 169 ÷2

=-7 +- 13 ÷2

Now,

Either x=-7+13÷2=6÷2=3

Or x=-7 -13 ÷2=-20÷2=-10

Hence, ans is (C) x=-10 and x=3

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$\qquad\qquad\huge\underline{{\sf Answer}}$

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Question

nika2105 [10]

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