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Questions related to Quadratics

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ashwinkandel:
Find the range of value of c, given that, for all values of x, x^2+5x+c>2

........:
c>33/4

ashwinkandel:
Can you show me the process?? how did u take out the answer

astarmathsandphysics:
Complet the squuare
x^2+5x+c>2
(x+2.5)^2-2.5^2+c>2
(x+2.5)^2-2.5^2+c-2>0
(x+2.5)^2 is a square number so must be greater than zero, so
-2.5^2+c-2>0 so c>2.5^2+2=8.25

ashwinkandel:
I am little bit confused with the last steps of the solution:
(x+2.5)^2 is a square number so must be greater than zero, so
-2.5^2+c-2>0 so c>2.5^2+2=8.25
I accept that (x+2.5)^2 is always greater than zero, then how can we say that -2.5^2+c-2 is also greater than zero?

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