That's not true at all.
If a=2 and b=3 . . . then
2 · a · b = 12
but
a² + b² = 13 .
This doesn't satisfy your statement, because 12 and 13 are not equal.
Right off hand, it looks to me as if your statement is true
ONLY if
|a| = |b| ('a' = plus or minus 'b')
and NOT for any other pairs of numbers.
Answer:
C.
Step-by-step explanation:
Yes, because the area of the base of a triangular pyramid with equilateral triangles for faces is the same as the area of each face.
So the surface area is 64 * 4 which is 256
The solution will be: 
<em><u>Explanation</u></em>
The given inequality is: 
First we will subtract
from both sides. So.....

Now we will subtract 13 from both sides. So.....

Then we need to divide both sides by -3. As here we are <u>dividing the inequality by a negative number, so we need to switch the inequality symbol</u>. So, we will get.......

Thus, the solution will be: 