OK dose solve for x we n33d to get x by its self so 42/7 is 6 x is 6
40 + 2x - 30 + x + 20 = 180
3x + 30 = 180
3x = 150
x = 50
m<B = 2x - 30
m<B = 2(50) - 30
m<B = 100 - 30
m<B = 70
Step 
<u>Find the slope of the given line</u>
Let

slope mAB is equal to

Step 
<u>Find the slope of the line that is perpendicular to the given line</u>
Let
CD ------> the line that is perpendicular to the given line
we know that
If two lines are perpendicular, then the product of their slopes is equal to 
so

Step 
<u>Find the equation of the line with mCD and the point (3,0)</u>
we know that
the equation of the line in the form point-slope is equal to

Multiply by
both sides


therefore
the answer is
the equation of the line that is perpendicular to the given line is the equation 
Are you sure it is correct because for each one your just doubling the number. 2+2=4. 4+4=8. 8+8=16. I think its suppose to be 16+16= 32 and so on, but I may be wrong