Can someone help with numbers 1 and 2 for both of them tell me the answer and how you get it

a = 20, b = 8

Step-by-step explanation:

Using Pythagoras' identity

The square on the hypotenuse is equal to the sum of the squares on the other 2 sides.

(1)

a² + 15² = 25²

a² + 225 = 625 ( subtract 225 from both sides )

a² = 400 ( take the square root of both sides )

a = = 20

(2)

b² + 6² = 10²

b² + 36 = 100 ( subtract 36 from both sides )

b² = 64 ( take the square root of both sides )

b = = 8

687.09 dollars       happy now

step-by-step explanation: 6870

1857 times .63 equals 1169.91 subtract that from 1857 you get 687.09

sorry not sure

step-by-step explanation: