Okay, let's add the two x values.
10x + 75 = 5x = 110
15x + 75 = 110
Now let's minus 75 from each side.
15x = 35
Now let's divide each side by 15.
x = 2.333333333
9 x 2 = 18
6 x 3 = 18
and 18 x 1 = 18
1) The triangles are similar, so correponding sides have the same ratio.
.. 3x/20 = (4x +2)/28
.. 3x/5 = (4x +2)/7 . . . . . . . multiply by 4
.. 7*3x = 5(4x +2) . . . . . . . multiply by 35 = 5*7
.. 21x = 20x +10 . . . . . . . . eliminate parentheses
.. x = 10 . . . . . . . . . . . . . . . subtract 20x
2) The triangles are similar, so corresponding measures have the same ratio.
.. x/42 = 10/15
.. x = 42*(10/15) = 28
3) The third angle of triangle ABC is 180° -20° -80° = 80°. Then two of the angles of ABC match those of JKL. The 3rd answer selection is appropriate.
To know for sure I’d need to see the bar graph. But with in the information present the answer would be 12.25% or 1/8