Answer:
c = 9
Step-by-step explanation:
Since angle d and 59 are on a right angle (indicated by the small square)
We can equate the sum of these angles to 90:
d+59=90
Now we subtract 59 from both sides:
d+59-59=90-59
d=31
Since angles d,c and 140 are on a straight line we can equate the sum of these 3 to 180:
c+d+140=180
Substitute d with 31 from previous working out:
c+31+140=180
Simplify:
c+171=180
Subtract 171 from both sides:
c+171-171=180-171
Simplify:
c= 9
