Question

plz tell me 20 or 21 or 22 both parts with full explanation

Answer 1

20) ( x + 11 )²

1. you must square the x =x²

2. then multiply the x by 11 and 2, so 11 x 2 =22, 22 × X = 22x

3. then you square 11, = 11 x 11 = 121

= x² + 22x + 121

22) (5a + 2b) ³

1. you expand by,

(5a + 2b)² + (5a + 2b)

so first step you do the same thing,

2. 5a is squared = (5a)² =25a²

3. then you multiply 5a by 2b by 2, =( 5a x 2b) x2 = 20ab

4. then you must square 2b, =4b²

so you should have 25a² + 20ab +4b² + (5a +2b)

= 25a² +20ab +4b² + 5a + 2b

hope i am right and have helped :)