Respuesta :

michellechitsaka

Answer:

M=7

Step-by-step explanation:

Angles on a line =180

Middle Angel =90 degrees

5m+3+8m-4+90=180

5m+8m+3-4+90=180

13m-1+90=180

13m+89=180

13m=180-89

13m=91

13m÷13=91÷13

M=7

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