Factorise the following quadratic polynomials by splitting the middle term

$x^{2}-12 x+20$

Is $(x-1)$ is a factor of $3 x^{2}+7 x-10 ?$

$4 x^{2}-20 x+25=(\ldots \ldots \ldots)^{2}$

Factorise the following quadratic polynomials by splitting the middle term

$x^{2}+2 x-143$

Write the coefficients of $x^{2}$ in each of the following polynomials

$x^{3}+27$

Verify whether the following are True or False:

$-3$ is a zero of $x-3$