Express the following number as a product of prime factors.

$256$

Factorise $a^2\left(b+c\right)+b^2\left(c+a\right)+c^2\left(a+b\right)+3abc$.

Factorise: $6a(a–2b)+5b(a–2b)$.

Factorise:$16(2p–3q{)}^2–4(2p–3q)$. 

Factorise: $x^2–ax–bx+ab$.

Factorise:$ar+br+at+bt$. 

Express the following number as a product of prime factors.

$343$

Factorise: $3(a–2b{)}^2-5(a–2b)$

Factorise: $2a+6b–3(a+3b{)}^2$.

Factorise:$x(x+3)+5(x+3)$ 

Factorise:$(x+y)(2x+5)–(x+y)(x+3)$ 

Factorise: $x^3(2a–b)+x^2(2a–b)$

Factorise: $16a^2-24ab$.

Factorise: $9a(3a–5b)–12a^2(3a–5b)$.

Factorise: $x(a–3)+y(3 –a)$

Factorise: $(x + 5{)}^2–4(x+5)$