What is the measure of angle b in the triangle?

B = 70

Step-by-step explanation:

The sum of the angles of a triangle add to 180 degrees

A + B + C = 180

40 + 2x-30 + x+20 = 180

Combine like terms

3x + 30 = 180

Subtract 30 from each side

3x+30-30 = 180-30

3x = 150

Divide by 3

3x/3 =150/3

x = 50

We want to find angle B

B = 2x-30

   =2(50) - 30

   = 100 - 30

   = 70

395.84

step-by-step explanation:

2πrh+2πr²

2 (pie)(radius)(height)+2(pie)(radius)^2