First change them all into either fractions or decimals. Decimals are probably easier though. 1/5 = 0.2; 12/25 = 0.48; 4/5 = 0.8
Order: 0.2, 0.35, 0.48, 0.5, 0.8
Then you change the decimals that you converted back into the fraction form
Answer: 1/5, 0.35, 12/25, 0.5, 4/5
The easiest way to tell whether lines are parallel, perpendicular, or neither is when they are written in slope-intercept form or y = mx + b. We will begin by putting both of our equations into this format.
The first equation,

is already in slope intercept form. The slope is 1/2 and the y-intercept is -1.
The second equation requires rearranging.

From this equation, we can see that the slope is -1/2 and the y-intercept is -3.
When lines are parallel, they have the same slope. This is not the case with these lines because one has slope of 1/2 and the other has slope of -1/2. Since these are not the same our lines are not parallel.
When lines are perpendicular, the slope of one is the negative reciprocal of the other. That is, if one had slope 2, the other would have slope -1/2. This also is not the case in this problem.
Thus, we conclude that the lines are neither parallel nor perpendicular.
An obtuse triangle has one obtuse angle, or an angle that measures more than 90° but less than 180°. Options 1 and 2 are not correct, because these are acute angles.
So, one of the angles must be 40°, and the other may be 100° or 120°.
The measures of the angles in a triangle add up to 180°.

The other two angles are 40° and 100°.
I believe the answer to this is F and i think D also
1.) 12+x is greater than or equal to 20
2.) 14 is greater than it equal to x
3.) 50 is greater than or equal to x