Question

Factorise 9 (b+2a)square-4asquare​

Answer 1

Answer:

9b^2+36ab+20a^2

Step-by-step explanation:

9 ( b+ 2a) ^2 -4a^2

(a+b)^2= a^2+2ab+(b)^2

9(b^2 + 2×b×2a + (2a)^2)-4a^2

9(b^2+4ab+4a^2) -16a^2,

9b^2+ 36ab + 36a^2 -16a^2

9b^2+36ab +20a^2

Answer 2

Answer:

9(b+2a)²-(4a)²

9(b²+4a²+4ab)-(4a)²

9(b²+4a²+4ab)-16a²

9b²+36a²+36ab-16a²=0

9b²+ 20a²+36ab=0