Find the value of each variable and the measure of arc lm. the diagram is not drawn to scale. a. x= 100° y= 40° arc lm= 80° c. x=100° y= 50° arc lm= 200° b. x= 180° y= 40° arc lm = 80° d. x= 90° y= 50° arc lm= 100°

the answer is d.x= 90°

y= 50°

arc lm= 100°

i got this one chief

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.