The answer for finding the slope is -1/2
2 x 3.99 = 7.98
3 x 4.49 = 13.47
1 x 4.99 = 4.99
Total: 26.44
50.00 - 26.44 = 23.56
The answer to your Q is 4
#1 is similar to write it out it’s triangle FHG ~ triangle KJL #2 is also but #3 and #4 aren’t
If you find a first you will be able to find b a little faster then it is super easy after that you got this!