3x + 2y = 11
y = 5x -1
Using substitution
3x + 2(5x-1) = 11
3x + 10 x -2 = 11
13x = 13
x = 1
but, y= 5x -1
y = 5 (1)- 1
= 4
Therefore, y =4 and x = 1
Question 2
Using linear combination method
2x -3y = 13
x+2y = -4 multiplying the second equation by 2 to eliminate x
we get
2x - 3y = 13
2x + 4y = -8 ( subtracting the two equations)
-7y = 21
y = -3
To get x we substitute y with -3 in one of the equation
x = -4 -2y
x = -4 - 2(-3)
x = 2
Therefore, the value of x = 2 and y =-3
Question 3
The first thing is to get a table of values for each of the equation using at least three values of x, this gives you at least three coordinates that can be used to plot the lines on the Cartesian plane.
That is;
For; y = (1/2)x + 3
x y
(2 , 4)
(4, 5)
(6, 6)
And for -3x +y = -2 which is the same as y =-2 +3x
x y
(0, -2)
(1, 1)
(2, 4)
Then, plot the two lines on the plane using the above coordinates,
The solution will be the point of intersection of the two lines (where the two lines plotted meet)