Question

if the polynomial x^ - 15 - m (2x - 8) has equal zeroes, find the value of m

Answer 1

Heya !!




X² - 15 - m ( 2x - 8 )




X² - 15 - 2mX + 8m




X² - 2MX + 8M - 15




Here,


A = 1 , B = -2M and C = 8M - 15





Discriminant ( D ) = 0




B²-4AC = 0


(-2M)² - 4 × 1 × (8M - 15 ) = 0





4m² - 32m + 60 = 0




4 ( m² - 8m + 15 ) = 0





m² - 8m + 15 = 0




m² - 3m - 5m + 15 = 0



m ( m - 3 ) - 5 ( m - 3 ) = 0





( m - 3 ) ( m - 5 ) = 0




( m - 3 ) = 0 OR ( m - 5 ) = 0




m = 3 or m = 5.

Answer 2

$2x - 8 = 0 \\ x = \frac{8}{2} \\ x = 4 \\ now \: put \: the \: value \: ofx \\ {x}^{2} - 15 - m \\ {4 }^{2} - 15 - m \\ 8 - 15 - m \\ m = - 7$
the value of m is-7