M 2 = aº, m 3 = bº, m 41
a
b
a + b
a-b

m,4+ a+b

Step-by-step explanation:

an exterior angle equals the sum of the 2 opposite interior angles

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.

arithmetic sequence: a sequnce in which the diffrence between any two consecutive terms is the same

step-by-step explanation: