Answer:
25%
Step-by-step explanation:
Price reduction = 20 - 15 = $ 5
Percent decrease of price = (5/20)*100 = 5*5 = 25%
Given:
M=(x1, y1)=(-2,-1),
N=(x2, y2)=(3,1),
M'=(x3, y3)= (0,2),
N'=(x4, y4)=(5, 4).
We can prove MN and M'N' have the same length by proving that the points form the vertices of a parallelogram.
For a parallelogram, opposite sides are equal
If we prove that the quadrilateral MNN'M' forms a parallellogram, then MN and M'N' will be the oppposite sides. So, we can prove that MN=M'N'.
To prove MNN'M' is a parallelogram, we have to first prove that two pairs of opposite sides are parallel,
Slope of MN= Slope of M'N'.
Slope of MM'=NN'.
Hence, slope of MN=Slope of M'N' and therefore, MN parallel to M'N'
Hence, slope of MM'=Slope of NN' nd therefore, MM' parallel to NN'.
Since both pairs of opposite sides of MNN'M' are parallel, MM'N'N is a parallelogram.
Since the opposite sides are of equal length in a parallelogram, it is proved that segments MN and M'N' have the same length.
Answer:
The answer is 1.
Step-by-step explanation:
Nobel gases have full shell of valence electrons, that is why they tend to not enter any chemical reactions because they are satisfied while metals have very few electrons in the valence shell, so they are active in any chemical reaction.