Answer:
x = 15
Step-by-step explanation:
10x - 30 and 3x + 15 are same- side interior angles and sum to 180° , so
10x - 30 + 3x + 15 = 180 , that is
13x - 15 = 180 ( add 15 to both sides )
13x = 195 ( divide both sides by 13 )
