x2+8x−15=0
x2−2x−15=0
x2−8x−15=0
x2+2x+15=0
Correct answer is B
x2−(sum of roots)x+(product of roots) = 0
4x2−4x−15=0
Divide through by 4
=x2−x−154=0
=x2−x+(−154)=0
=x2−(1)x+(−154)=0
sum of roots =1
= m + (m + 4) = 1
=2m+4=1
=2m=-3
=m=-32
The equation whose roots are 2m and 2m+8
2m=2×-32=−3and 2m+8=2×−32+8=5
=x2−(−3+5)x+(−3)(5)=0
=x2−2x+(−15)=0
∴x^2-2x-15=0
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