Question

( (b, d) )
Let the roots be ( alpha ) and ( beta ). ( alpha+beta=8,|alpha-beta|=10 )
( (alpha-beta)^{2}=100 )
( (alpha+beta)^{2}-4 alpha beta=100 )
( alpha beta=-9 )
( therefore x^{2}-8 x-9=0 Rightarrowleft(x^{2}-8 x-9right)=0 )
or ( -left(-x^{2}+8 x+9right)=0 )

# Two numbers whose sum is 8 and the absolute value of whose difference is 10 are roots of the equation (a) x2 - 8r+9=0 (b) x2 - 8x - 9=0 (c) x2 + 8x -9=0 (d)-(-x2 + 8x +9)=0

Solution