Question

if 2ab+b=9 and ab=-4 then the value of 4a2+b2=?

Answer 1

Answer:

25

Step-by-step explanation:

Here : m=2a , n=b

mn = 2ab

as (m+n)²=m² +n² +2mn

(2a+b)²=4a² + b² +4ab

by substituting values from the question

9²=4a² + b² -16

4a² + b² =25

Answer 2

Answer:

65

Step-by-step explanation:

ab= -4

a=4  b=-1  ab= (axb) = 4x-1 = -4

4a^2+b^2 =

4(4x4) + (-1x-1)

64+1 = 65