Can you solve this for me please?​

19: 106

20: 79

21: 70

Step-by-step explanation:

Circle upper left

The central angles all add up to 360 degrees

BC + CD + 148 = 360

But CD = BC

2BC + 148 = 360            Subtract 148 from both sides

2BC = 360 - 148             Combine

2BC = 212                       Divide by 2

BC = 106

20

3 of the 5 arcs are marked as being equal.

Let each of them be called  = x

3x + 41 + 82 = 360          Combine

3x + 123  = 360                Subtract 123 from Both sides.

3x = 360 - 123

3x = 237

x = 237 / 3

x = 79

BC = 79

21

Unless DE and FC are diameters, this can't be solved. I will assume they are.

FB + 48 + 22 = 180.

FB + 70 = 180

FB = 110

FC = FB + BD + DC

180 = 110 + 22 + DC

180 = 132 + DC

DC = 180 - 132

DC = 48

BC = BD + DC

BC = 22 + 48

BC = 70

5x+40

5(x + 8)

7x - 49

7(x - 7)

18x + 9

9(2x + 1)

15x - 10

5(3x - 2)

step-by-step explanation:

for number one all you have to do is factor 5 out of 5x + 40

for number 2 factor 7 out of 7x - 49

for number three factor 9 out of 18x + 9

for number four factor 5 out of 15x - 10