Answer:
Correct choice is C). mn=ac
Step-by-step explanation:
Given statement is that the first step in factoring a trinomial of the form is to find two numbers, m and n, such that m + n = b and _____.
We know that when we factor polynomial of type 
,product of both numbers m and n must be same as product of a and c.
Hence correct choice is C). mn=ac
Answer: x=r^2
+
10
r
+
25
The conditional, <span>If four points are non-coplanar, then they are non-collinear, </span>is true:
This is, coplanarity is a necessary condition to be collinear.
The converse, <span>If four points are non-collinear, then they are non-coplanar, is false.
A counterexample that disproves this statement is the 4 vertices of a paralelogram, of course they are in a same plane and are not collinear.
</span>
40.7..........................
