Let x represent the number of song downloads and let y represent the total cost 
y=0.95x+70
        
             
        
        
        
300. When the number is 5 and up, then you round up to the next digit. For example, 350 would round up to 400. But seeing as it is 346, you round down. 
        
                    
             
        
        
        
Answer:
x = 5√2
y = 5√6
z = 5√3
ΔABC ~ ΔBDC ~ ΔADB
Step-by-step explanation:
ΔABC, ΔBDC, and ΔADB are all similar triangles to each other.
By definition of similar triangles, the corresponding sides have the same ratios.
CD from ΔBDC corresponds to BD from ΔADB, and BD from ΔBDC corresponds to AD from ΔADB. So:
CD / BD = BD / AD
10 / x = x / 5
x² = 50
x = 5√2
Since ΔBDC is right, we can use the Pythagorean Theorem to solve for y:
CD² + BD² = BC²
10² + (5√2)² = y²
y² = 100 + 50 = 150
y = 5√6
Again, since ΔΔABD is right, we can use the Pythagorean Theorem to solve for z:
AD² + BD² = AB²
5² + (5√2)² = z²
z² = 25 + 50 = 75
z = 5√3