Respuesta :
Answer: 27
Step-by-step explanation: Half of the supplementary (180 degree) angle is 90 degrees so we know that the other half is also 90 degrees. so 3x+9=90
Subtract 9 3x=81 divide by 3
x=27
Answer: 27
Step-by-step explanation: Half of the supplementary (180 degree) angle is 90 degrees so we know that the other half is also 90 degrees. so 3x+9=90
Subtract 9 3x=81 divide by 3
x=27