Question

What is the discriminant of x^2=-14x-40

Answer 1

Step-by-step explanation:

x2+14x+40

We can Split the Middle Term of this expression to factorise it.

In this technique, if we have to factorise an expression like ax2+bx+c, we need to think of 2 numbers such that:

N1⋅N2=a⋅c=1⋅40=40

and,

N1+N2=b=14

After trying out a few numbers we get N1=10 and N2=4

10⋅4=40, and 10+4=14

x2+14x+40=x2+10x+4x+40

=x(x+10)+4(x+10)

Here (x+10) is common to both terms.

So the factorised form is=(x+4)(x+10)