Finding the mean is you have to add it all up:
49+55+52+46+47+42+38= 328
The divide it by the amount of numbers so, 329/7= 47.
Subtract 47 from every number then, but even if you get a negative number you gotta keep it a positive so just ignore it if you get a negative answer when subtracting, once you do that you would add up those answers you got so;
2+8+5+1+0+5+9= 30
Then divide it again, 30/7
Which then you get the M.A.D which is 4.3, rounded to the nearest ten.
When added, these two angles are supplementary, meaning that their sum is 180. This means that we can do the following to find x, and eventually DBC:
3x+67+4x+50=180
Simplifies to:
7x+117=180
Then by the Subtraction Prop. of Equality:
7x=63
Then divide by 7 on both sides to get that x=9.
We then substitute 9 into angle DBC.
4(9)+50
=36+50
DBC=86
:)
One possible system of two equations is ...
x = -2
y = -3 .
