Here, we want to factorize the given quadratic trinomial
Firstly, we multiply the first and last terms;
[tex]2z^2\text{ }\times(-21)=-42z^2[/tex]
Now, we need two terms, which are factors of this product and when added, will give the middle term
We know that z is imperative, let us just list out the factors of -42
We have to consider the positive and the negative numbers
So, we have the factors as follows;
1, - 1 , 2, -2 , 3 , -3 , 6, -6 , 7 , -7 , 14, -14 , 21, -21 , 42, -42
Now, we need two numbers, such that when we add, they give the mi
