Question

Factorise: 9x2 + 16y2 + 25z2 + 24xy – 40yz - 30xz.​

Answer 1

Answer:

Step-by-step explanation:

9x² + 16y² + 25z² + 24xy - 40yz - 30zx

= (3x)² + (4y)² + (5z)² + 2(3x)(4y)  - 2(4y)(5z)  - 2(3x)(5z)

= (3x)² + (4y)² + (-5z)² + 2(3x)(4y)  + 2(4y)(-5z)  + 2(3x)(-5z)

= (3x)² + (4y)² + (-5z)² + 2(3x)(4y)  + 2(4y)(-5z)  + 2(3x)(-5z)

(a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ac

a = 3x

b = 4y

c = - 5z

= ( 3x + 4y - 5z)²

9x² + 16y² + 25z² + 24xy - 40yz - 30zx =  ( 3x + 4y - 5z)²