4x^2-25= (2x)^2-5^2=(2x-5)(2x+5)
Used: a^2-b^2=(a+b)(a-b)
See what number goes in to 5 and 20 and then dive
I set Jon an equation and solved for number of hours
A would be the correct answer because he is up in elevation so that makes the 1200 positive and he goes down 20.4 which is negative and is goes that far down!!
hope this helps
