
We know that, in ∆ABC,
∠A+∠B+∠C = 180°
But the triangle is right angled at C
ie., ∠C = 90°
Therefore, ∠A+∠B+ 90° = 180°
⇒ ∠A + ∠B = 90°
Therefore, <u>cos(A + B) = cos 90º = 0</u>
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:
50% off :)
Step-by-step explanation:
use the purple coupon to take off half of the whole price so you spend less overall. And the only requirement is that it needs to be over the price of 350 (originally) , so your item is eligible.
Answer:
819÷13=63
Step-by-step explanation:
you divide 819 by 13 and you get 63
answer is the first one and the last 2