I need help on question 6.
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Answer: 135 degrees
Step-by-step explanation:
First you now that ABD+DBC=180 degrees
Subsitute so you get: (5x+10)+(2x-5)=180
Solve:
(5x+10)+(2x-5)=180
=> 7x+5=180
=> 7x=175
=> x= 25
Plug in 25 :
ABD= 5*25+10=135
And there is your answer