Answer:
21/10
Step-by-step explanation:
Trust Me

This result is actually true for any exterior angle. The exterior angle of a triangle is equal to the sum of the two remote angles, and above is a short proof of it.
Hello from MrBillDoesMath!
Answer:
The first choice ( -12, 20)
Discussion:
Using matrix multiplication we find the equations:
1x + 1y = 8 (A)
2x + 3y = 36 (B)
Next, compute
2(A) - B =>
(2x + 2y) - (2x + 3y) = 2*8 - 36 =>
(2x - 2x) + ( 2y-3y) = 16 - 36 =>
-y = -20 =>
y = 20
Substituting this y value in (A) gives
x + 20 = 8 =>
x = 8 - 20 =>
x = -12
The answer is the first choice ( -12, 20)
Thank you,
MrB
Answer: Undefined
Step-by-step explanation:
4y+x=12, 2x=24-8y
Isolate x by subtracting 4y
4y+x=12
x=12-4y
Plug the equation for x in to anywhere you see the variable x in the other equation
2(12-4y)=24-8y
Distribute 2
24-8y=24-8y
Get the variables on one side so add 8y (cancels out)
24=24
Can’t solve its undefined