Answer:
x = 9
Step-by-step explanation:
Of course I'll do very simple explanation!
every time you see a straight line (nondiagonal) it measures 180°.
so if we're trying to solve for x in this case, we'll subtract 180° - 40° = 140°.
Then use the statement to solve for x
[tex]10x+50=140[/tex]
[tex]10x-50[/tex] = - 50 Subtract 50 from both sides
[tex]10x[/tex] [tex]=[/tex] 90 Divide 10 from both sides
x = 9