Question

If the equation (a²+ b²) x² – 2 (ac + bd) x + c² + d² = 0 has equal roots, then
A. ab = cd
B. ad = bc
C. ad=vbc
D.ab=vcd

Answer 1

Answer:

( b) ad=bc

Step-by-step explanation:

equal roots = b²= 4ac

4 (ac+bd)² = 4 (a²+b²)(c²+d²)

a²c² + b²d² + 2acbd = a²c² + a²d² + b²c² + b²d²

a²d² + b²c² - 2adbc = 0

(ad-bc)² = 0 {by (a+b)²= a² + b² + 2ab}

ad-bc =0

ad=bc