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;
and 
.
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;
Put the value of x = a and y = -1;
(-1) = -(a) + 9
a = 9 + 1 = 10
Now, taking the second equation;
Put the value of x = a and y = -1;
0.5a = 6 - 1
0.5a = 5
a = 10
Since we get the value of a = 10 from the equations, so the value of a is 10.
-x ---------------- 1x
7y --------------- 12y
-12x^2 --------- 8x^2
a ----------------- -2a
6a^2------------ a^2
-5x^3 ---------- 15x^3
_____________________
you just have to match the terms which have the same power.
Hope it helps ^^
Answer: 75 degrees
Step-by-step explanation: supplementary means 180 so you do 180-105 which is 75
Step-by-step explanation:
17.0 there you go I hope this helped
Answer:
28. 120 degrees
29. 30 degrees
30. 56 degrees & 124 degrees
31. 72 degrees, 108 degrees, and 18 degrees
Step-by-step explanation:
We assign variable x for the answer we are looking for (28-29).
28.
Supplement means x + y = 180 degrees. We also know x = 2y. Substitution gives us 3y = 180 degrees, so y = 60 degrees and x = 120 degrees.
29.
Complement means x + y = 90 degrees. We are given 2x = y. Substitution brings us 3x = 90 degrees, x = 30 degrees.
30.
Supplement means x + y = 180 degrees. We are told that y = 2x + 12, so we substitute. This gives 3x + 12 = 180 degrees, x = 56 degrees. Substituting that back into the equation for y, we get 124 degrees.
31.
Supplement means x + y = 180 degrees. Complement means x + z = 90 degrees. Using our given info, we know y = 6z. We can substitute that in to get x + 6z = 180. Subtracting our second and third equations, we get 5z = 90, z = 18 degrees. Therefore, x = 72 degrees, y = 108 degrees.
