Answer:
x = 28
Step-by-step explanation:
Triangle ABP and triangle CDR are similar. Thus, we can solve this problem for x using an equation of proportions:
hypotenuse leg length
15+42 10+x
---------------- = ----------
42 x
Then (15+42)x = 42(10+x) after cross multiplication
57x = 420 + 42x
Subtracting 42x from both sides, we get
15x = 420.
Dividing both sides by 15 results in
x = 28
