Respuesta :
Answer:
25
Step-by-step explanation:
Since AC is similar to CE, we can say that they have equal lengths. We are given CE, DE, and BC. To solve this, we can solve for the length of CE (equal to AC) and then subtract that from BC.
To solve for CE, we are given DE and CE. We know that DE is 1/2 of CE because D is the midpoint of CE. Therefore,
7x-1 = 1/2(10x+18)
expand
7x-1 = 5x + 9
add 1 to both sides to separate the 7x
7x = 5x + 10
subtract 5x from both sides to separate the x
2x = 10
divide both sides by 2 to separate the x
x=5
Therefore, DE = 7(5)-1 = 34 and CE = 10(5) + 18 = 68 = AC.
Using x=5, we know that BC = 9(5) -2 = 43
Therefore, AB = AC-BC = 68-43 = 25
D is the midpoint of CE, so if you draw a line with those three points, it'll look like C-D-E.
Since DE = 7x-1, which also means CD = 7x-1.
CD + DE = CE, so (7x-1)+(7x-1) = 10x+18.
Therefore, x = 5 and CE = 68.
Since AC is congruent to CE, AC = 68.
Assuming the point B is somewhere between AC.
Since BC = 9x-2 and x = 5, which means BC = 43.
AC - BC = AB, so 68 - 43 = 25.
Therefore, AB = 25