[tex]\text{Adjacent angles on a straight line sum up to 180} \textdegree[/tex]
[tex]\text{Therefore }\measuredangle 1 + \measuredangle 2 = 180 \textdegree[/tex]
[tex]\text {Since } \measuredangle 1 = 6x+50 \text { and } \measuredangle 2 = x+40[/tex]
[tex](6x+50) + (4x+40) = 180[/tex]
[tex]6x+50 + 4x+40 = 180[/tex]
[tex]10x+90 = 180[/tex]
[tex]10x = 180 - 90[/tex]
[tex]10x = 90[/tex]
[tex]x = 9[/tex]
Answer: x = 9
