Answer:
thank you!!
Step-by-step explanation:
mike charges 100 dollars service charge plus 65 dollars per hour.
amy charges 40 dollars service charge plus 80 dollars per hour.
the cost to repair from mike is 100 + 65 * x.
the cost to repair from amy is 40 + 80 * x.
let x = 3 and you get:
the cost to repair from mike is 100 + 65 * 3 = 295 dollars.
the cost to repaid from amy is 40 + 80 * 3 = 280 dollars.
as long as the time to repair is 3 hours or less, the cost to repair will be cheaper from amy.
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 number of trees at the begging of the 4-year period was 2560.
Step-by-step explanation:
Let’s say that x is number of trees at the begging of the first year, we know that for four years the number of trees were incised by 1/4 of the number of trees of the preceding year, so at the end of the first year the number of trees was
, and for the next three years we have that
Start End
Second year
-------------- 
Third year
-------------
Fourth year
--------------
So the formula to calculate the number of trees in the fourth year is
we know that all of the trees thrived and there were 6250 at the end of 4 year period, then
⇒
Therefore the number of trees at the begging of the 4-year period was 2560.