Can someone help with this please?

<4 = 81

Step-by-step explanation:

we know that all the interior angles of a triangle will equal 180

so <1 + <2 + <3 = 180

we know that <4 is the exterior angle to <3

the exterior angle is equal to the angles opposite to its interior

<3 is the interior angle to <4

<1 and <2 are the angles opposite to <3

so <4 = <1 + <2

<4 = 42 + 39

<4 = 81

step-by-step explanation:

once you graph it hit 2nd (the blue button) and graph

that takes you to a table of coordinates

on the left is x coordinates and on the right is y coordinates and an empty box

(you may have to scroll up/down in order to get ( x, 0)

80° is the measure of gh

step-by-step explanation:

circle f is congruent to circle j

we have two circle with center f and j.

both circles are congruent. the radius of the circle would be equal.

see the attachment for the circle.

we are given ∠efd ≅ ∠gjh

therefore, arc (ed) = arc (gh)     (∴ circle f is congruent to circle j)

but ∠dfe=80°=arc (ed)

therefore, arc (gh) = 80°

thus, 80° is the measure of gh