Answer:
You use trigonometry.
Step-by-step explanation:
You can use soh cah toa. Basically you pic one side and if the interior angle is opposite or next to it, you you soh, or cah, or toa, it's based on where the angle is.
2(x-3)=7x-31
2x-6=7x-31
-7x -7x
----------------
-5x-6=-31
+6 +6
--------------
-5x=-25
Divide by -5
x=5
3x-2(x+5)=-3+18
15
3x-2(x+5)=15
3x-2x-10=15
x-10=15
+10 +10
--------------
x=25
D, it’s a function because the Y and X values have its own numbers , and vertical are functions . Horizontal is not a function
Discriminant = square root (b^2 -4*a*c)
square root (64 -4*1*12) =
square root (16) =
4
Therefore it has 2 rational soltions