Respuesta :

rcbrady1

Answer:

87.4°

Step-by-step explanation:

(3x + 8) + (3x + 18) + (7x + 9) = 180

3x + 8 + 3x + 18 + 7x + 9 = 180

add the common numbers

13x + 35 = 180

subtract 35

13x = 145

divide 13

x = 11.2

then plug it back in to m<3

7(11.2) + 9

78.4 + 9

= 87.4°

good job