Answer:
3 = ?
Step-by-step explanation:
The triangles are similar, so we can use ratios
15 12 -2
------ = --------------
15+? 12
15 10
------ = --------------
15+? 12
Using cross products
15 * 12 = 10 ( 15+?)
180 = 10 ( 15+?)
Divide each side by 10
18 = 15+?
Subtract 15 from each side
18-15 = 15+?-15
3 = ?
