Posted by Jon on .
1)Find x in the solution of the system 3x+y=2 and 2x3y=16
A)2
B)4
C)18/11
D)10/11
I chose A
3x+y=2 times 3 = 9x+3y=6
2x3y=16 times 1 = 2x3y=16
11x/11 = 22/11x = 2
2)Find the coordinates of the vertices of the figures formed by y < x + 2, x + 2 < 6, and y > 2
A)(0,0),(2,4),(8,2)
B)(4,2),(2,4),(8,2)
C)(4,2),(4,2),(8,2)
D)(2,4),(2,4),(8,2)
I chose B
this one confused me this is all the work to show:
2 < 4 + 2
2 + 4 < 6
2

Algebra 
Reiny,
Your inequations form the boundaries of the figure.
So change the < or > to an equal sign, then solve them in pairs.
You should get 3 sets of intersection points.
Solve the pairs of equations just like you did #1. 
Algebra 
Jon,
ok im stuck after this:
y = x + 2
x + y = 6
y = 2 
Algebra 
Guido,
I will do number one only.
We have this:
(1)Find x in the solution of the system 3x + y = 2 and 2x 3y = 16.
(A)2
(B)4
(C)18/11
(D)10/11
Your choice = (A)
We have a system of linear equations in two variables.
Here are the two equations:
3x + y = 2...Equations A
2x 3y = 16...Equation B
I will first isolate y in Equation A.
3x + y = 2
y = 3x + 2....I will plug the quantity (3x + 2) in Equation B to find the value of x.
2x  3y = 16
2x  3(3x + 2) = 16
2x + 9x  6 = 16
11x  6 = 16
11x = 16 + 6
11x = 22
x = 22/11
x = 2
Your choice is correct!
Good job!