Sorry, it's late, and I'm a bad explainer.
The error is adding (2x-12) with x and 30. This is wrong because you are adding the angles inside the triangle and you are assuming that (2x - 12) is the unlabeled angle INSIDE the triangle, when it is the exterior angle/outside of the triangle.
A straight line is also 180°.
(2x - 12) + ? = 180
30 + x + ? = 180
If you look at the equations, and put parentheses around 30 + x, (30 + x) and (2x - 12) should be the SAME NUMBER. So you could set them equal to each other to find x. (or you could also look at the picture and see that they both need/are missing the same angle)
2x - 12 = 30 + x
x = 42
Now you plug 42 into the exterior angle equation
2(42) - 12 = 84 - 12 = 72°
To complete the table, plug in the values into the equation (y=2x+3) if you already have the y then solve for x using inverse operations, and if you have the x then just use order of operations like normal
Step 1: Y= 27 - 4x
To find X - intercept / zero, substitute Y = 0
0 = 27 - 4x
Step 2: 0 = 27 - 4x
Move variable to the left-hand side and change it's sign.
4x = 27
Step 3: 4x = 27
divide both sides of the equation by 4
X = 27/4
solution: X = 27/4
Alternate form: X = 6 3/4, X = 6.75
Is one of the answer choices no solution because that’s what I got.
