-21 - (-13)
-21 + 13
= -8
The answer B)
The two are perpendicular to each other because the two slopes are negative reciprocals
(Y2 - Y1) / (X2 - X1)
First slope:
( 1 - (-1)) / (-11 - (-6))
2/-5
Second slope:
(-13 - (-8)) / (-5 - (-3))
-5/-2 or 5/2
You know when two aliens are perpendicular when you multiply the two slopes and get -1 as the product
-2/5 X 5/2 = -1
Thus the two lines are perpendicular to each other.
Here is my table of points:
Let x and y be the two numbers
Saying "The sum of two numbers is 27" means x+y = 27. The term "sum" is the result of adding. So the first equation is x+y = 27
The second equation is y = x+3 where we assume that y is the larger number of the pair.
So your system of equations will be
x+y = 27
y = x+3
Use substitution to solve this system.
x+y = 27
x+( y ) = 27
x + (x+3) = 27 ... notice how y has been replaced with x+3 (since y = x+3)
x+x+3 = 27
Solve for x and then use this to find y. I'll let you finish up.
If you need more help, then please let me know.
