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°
Answer:
63/100
Step-by-step explanation:
Im Pretty sure this the correct answer
Answer: 84.09%
Step-by-step explanation:
1. 220-30=? ?=185
2. Divide 185 by 220 (as a fraction, 185 out of 220 is 185/220 which also means divide) 185 divided by 220 is about 0.8409
3. Multiply 0.8409 by 100 (since there is two zeros in 100 we can move the decimal to the right twice which gets you 84.09
Answer:
3 < x < 17
Step-by-step explanation:
Given 2 sides of a triangle then the third side x is in the range
difference of 2 sides < x < sum of 2 sides , that is
10 - 7 < x < 10 + 7
3 < x < 17
Answer:
-0.43
Step-by-step explanation: