Question

solve please see atachment​

Answer 1

Answer:

B = 25 degree

Step-by-step explanation:

Let the straight line be named ABCD

such that angle ABD =(3a+10)

angle CBD= 2b

ABC is straight line and sum of all angles on a straight line in 180 degree

so, (3a+10)+2b = 180

given a= 40 so,

⇒ (3*40+10)+2b = 180

⇒ 2b + 130 = 180

⇒2b= 50

b= 25 degree