Answer :

Answer:

Below in bold

Step-by-step explanation:

b = 40.

d = 70

From the diagram:

a = c   (because they are both opposite the equal angles), so:

2a + 2c + 2*40 + 2*70 = 360

But a = c so:

2a + 2a + 80 + 140 = 360

4a + 80 + 140 = 360

4a = 360 - 220 = 140

a = 35

so c = 35.