Answer:
The value of a is 10.
Step-by-step explanation:
We are given with the following pair of the linear system of equations below;
[tex]y = -x+9[/tex] and [tex]y = 0.5x-6[/tex].
Also, the solution is given as (a, -1).
To find the value of 'a', we have to substitute the solution in the equation because it is stated that (a, -1) is the solution of the given two equations.
So, the x coordinate value of the solution is a and the y coordinate value of the solution is (-1).
First, taking the equation;
[tex]y = -x+9[/tex]
Put the value of x = a and y = -1;
(-1) = -(a) + 9
a = 9 + 1 = 10
Now, taking the second equation;
[tex]y = 0.5x-6[/tex]
Put the value of x = a and y = -1;
[tex](-1) = 0.5(a)-6[/tex]
0.5a = 6 - 1
0.5a = 5
[tex]a=\frac{5}{0.5}[/tex]
a = 10
Since we get the value of a = 10 from the equations, so the value of a is 10.
