Answer:
x=9
Explanation:
We can use proportions to solve this problem. Put the side of the small triangle over the side of the large triangle
6+x 12
--------- = ---------
25 32-12
6+x 12
--------- = ---------
25 20
Using cross products
20 (6+x) = 12*25
Distribute
120+20x = 300
Subtract 120 from each side
120-120 +20x = 300-120
20x = 180
Divide by 20
20x/20 = 180/20
x = 9