Answer:
x = 1
y = 5
z = 2
Step-by-step explanation:
System of equations:
6x - 2y + z = -2
2x + 3y - 3z = 11
x + 6y = 31
Isolate one variable in any of the equations:
x + 6y = 31
x = 31 - 6y
Plug in this value for x in another equation:
6(31 - 6y) - 2y + z = -2
186 - 36y - 2y + z = -2
186 - 38y + z = -2
-38y + z = -188
z = -188 + 38y
Plug in these values in the remaining equation:
2(31 - 6y) + 3y - 3(-188 + 38y) = 11
62 - 12y + 3y + 564 - 114y = 11
626 - 12y + 3y - 114y = 11
626 - 9y - 114y = 11
626 - 123y = 11
-123y = -615
y = 5
Plug in value of y into our other answers to solve for x and z:
x = 31 - 6(5)
x = 31 - 30
x = 1
z = -188 + 38(5)
z = -188 + 190
z = 2
Check your work:
6x - 2y + z = -2
6(1) - 2(5) + 2 = -2
6 - 10 + 2 = -2
-4 + 2 = -2
-2 = -2
Correct!
*Note there are several ways to solve for these types of problems. I used substitution*
Given : The Cost of Laptop in 2007 is $1250
Given : The Cost of Laptop in 2009 is $1100
Decrease in Price of Laptop from 2007 to 2009 : (1250 - 1100) = $150
A) Percent Decrease in the Price of the Laptop from 2007 to 2009 is :



Given : Decrease in Price of Laptop from 2009 to 2010 = $165
B) Percent Decrease in the Price of the Laptop from 2009 to 2010 is :



Answer:
No, (3, 1) is not a solution to this system.
Step-by-step explanation:
13x+17y=12
x+7y=19
-----------------
13(3)+17(1)=39+17=56, not 12
3+7(1)=3+7=10, not 19
Answer:
graph A.
Step-by-step explanation:
A is a positive linear graph because the dots are going up which means that something in the graph is increasing which is positive.
sorry if that is confusing hope this helps!