Can you help me with this assignment?

AC =5

BC =  12

AB = 13

Step-by-step explanation:

Since this is a right triangle, we can use the Pythagorean theorem

a^2 + b^2 = c^2

(n-1)^2 + (2n)^2 = (n+7)^2

FOILing

n^2-2n+1  + 4n^2 = n^2+14n+49

Combine like terms

5n^2-2n+1   = n^2+14n+49

Bring everything to the left

5n^2-2n+1 -n^2-14n-49  = n^2+14n+49-n^2-14n-49

4n^2 -16n -48 = 0

Divide by 4

n^2 -4n -12 = 0

Factor

( n-6)(n+2) =0

Using the zero product property

n-6 =0  n+2 =0

n=6    n=-2

Since the length cannot be negative

n=6

AC = n-1 = 6-1 =5

BC = 2n = 2*6 = 12

AB = n+7 = 6+7 = 13

x = 12

y = 1

for the points!