a+5 = a^2-25, a>0 then sum of the roots of the given equation and inequation will be

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18 Jul 2012 root

a+5 = a^2-25, a>0
then sum of the roots of the given equation and inequation will be

OPtion

1) 6
2) 1
3) -1
4) 11
5) -5
6) 12
7) 2
8) 9
9) 3
10) none of these

Solution

(a+5) = (a+5)(a-5)
so (a+5)(a-5) - (a+5) = 0
or (a+5)[(a-5)-1] = 0
or a= -5 and a = 6
since a>0 so only root is 6

Correct Option: 1 Best Solution (15)

priyanka   12 years AGO

bcoz 6+5=6^2-25
11=11
lhs=rhs
and this satisfies both equation and inquation.
so ans is 6

Like? Yes (4) | No (1)  

Sneha paliwal   12 years AGO

equation become as a^2-a-30=0
(a-6)(a+5)=0
a=6 ,a>0

Like? Yes (5) | No (2)  

R.K   12 years AGO

a+5=a^2-25
a^2-25-a-5=0
a^2-a-30=0
a^2+5a-6a-30=0
a(a+5)-6(a+5)=0
a+5=0, a-6=0
a=-5, a=6
if a>0
then roots are 6

Like? Yes (2) | No (1)  

Dipesh Agrawal   12 years AGO

a+5=a^2-25
a^2-a-30=0
a^2-6a+5a-30=0
a(a-6)+5(a-6)=0
(a-6)(a+5)=0
therefore a=6,-5
sum of the roots is 1

Like? Yes (1) | No (1)  

asim   12 years AGO

from given eq. a+5 = a^2-25
on solving we get a^2-a-30 =0
=> a^2-6a+5a-30 = 0
=> (a-6)(a+5) = 0
=> a= 6 , -5
BUT fom given inequation a>0
only a = 6 satisfies both condition
hence sum of roots is 6 ans.

Like? Yes (2) | No (2)  

Balakrishnan M   12 years AGO

a+5 = a^2-25
a^2-a-30=0
solve this equation the roots are a=6,-5 since given a>0.
The Sum of the roots = 6

Like? Yes (3) | No (3)  

jyotish r   12 years AGO

the solutions are a=6,-5 since a>0
a=6 so option 1 is the right answer

Like? Yes (1) | No (1)  

Fercy   12 years AGO

a^2-25-5-a=0
a^2-a-30=0
(a-60(a+5)=0
a=6 since a>0

Like? Yes (1) | No (1)  

Shiv Kumar   12 years AGO

a+5 = a^2-25
this equation has two roots... those are -5 and 6

since a>0, sum of the roots will be 6

Like? Yes (2) | No (2)  

B.Senthil Kumar   12 years AGO

solution is 6 and -5 so result is 6

Like? Yes (1) | No (1)  

Rakesh Kumar Kohli   12 years AGO

The roots of the given equation a+5 = a^2-25 are 6 & -5, but as a >0, the only satisfying both this condition is 6.
As 6 is the only root satisfying the condition so sum of roots is 6.

Like? Yes (1) | No (1)  

Mohammed Farook.S   12 years AGO

if a=6 then
lhs=6+5=11;
rhs=6*6-25=11;
so the ans is 6.

Like? Yes (1) | No (1)  

sunil chhuttani   12 years AGO

6+5 = 6^2-25 = 11

Like? Yes (1) | No (1)  

Arun   12 years AGO

a+5=a^2-25
a^2-a-30=0;
a^2-5a+4a-20=0;
a(a-6)+4(a-5)
a=6;
a=-4;
as a>0. so sum of roots will be 6

Like? Yes (2) | No (2)  

subash   12 years AGO

option is simple sum of roots is 6-5=1

Like? Yes (1) | No (2)