Find a and b if(a – b) + (a + b)i = a + 5i

1.	Find a and b if(a – b) + (a + b)i = a + 5i
Answer» (a – b) + (a + b)i = a + 5i Equating real and imaginary parts, we get a – b = a ……(i) a + b = 5 ……(ii) From (i), b = 0 Substituting b = 0 in (ii), we get a + 0 = 5 ∴ a = 5 ∴ a = 5 and b = 0

Answer»

(a – b) + (a + b)i = a + 5i

Equating real and imaginary parts, we get

a – b = a ……(i)

a + b = 5 ……(ii)

From (i), b = 0

Substituting b = 0 in (ii),

we get a + 0 = 5

∴ a = 5

∴ a = 5 and b = 0

Discussion