Problem 44
The term "bisect" means "cut in half".
Since BD bisects angle ABC, this means the smaller angles ABD and DBC are congruent.
angle ABD = angle DBC
x+15 = 4x-45
15+45 = 4x-x
60 = 3x
3x = 60
x = 60/3
x = 20
<h3>Answer: x = 20</h3>
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Problem 45
We use the same idea as the previous problem
angle ABD = angle DBC
2x+35 = 5x-22
35+22 = 5x-2x
57 = 3x
3x = 57
x = 57/3
x = 19
<h3>Answer: x = 19</h3>
This should help you here are the steps of your problem :)
2*(1/2)*r+2*r+1 = 9*(1/10) // - 9*(1/10)
2*(1/2)*r+2*r-(9*(1/10))+1 = 0
2*(1/2)*r+2*r-9/10+1 = 0
3*r+1/10 = 0 // - 1/10
3*r = -1/10 // : 3
r = -1/10/3
r = -1/30
r = -1/30
So your answer would be 1/30