Use proportions and use letters for unknown measurements
Answer:
36+63i
explanation:
1)
b: 3.75 since it is half of the segment that measures 7.5, this is proven because the line in the middle is a bisector of the top and bottom line indication that both half measure the same; 3.75
2) 15 not sure why
K=1/3
simplify each bracket, put all numbers on the left hand side, equal it to 0 and solve for k