Find the measure of each angle indicated.

let the opposite angle of 60° be x.

60°+ 80°+x=180°(by angle sum property)

140°+x=180°

x=180°-140°

x=40°

let the opposite angle of 65° be y

so, 40°,100°and y lie on a straight line so there sum is equal to the 180°

40°+100°+y=180°

140°+y=180°

y=180°-140°

y=40°

now 65°,y and ? are triangle so, there sum is equal to the 180°.

y+65°+?=180°

40°+65°+?=180°

105°+?=180°

?=180°-105°

?=75°

where is the rest of the

step-by-step explanation:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18