Write a full questions to understand. You have wrote half questions only
you need to find to find the value of x and y.
2x>(-15-5y)
x>(-15-5y)/2
now put this in to other equation and solve for y and then put the y value in and find x.
15,56^2=x^2+x^2
242,1136=2x^2
x^2= 242,1136:2=121, 0568
x≈11,003
2.5s=5m simplifies to 2m in 1s, 3m in 1.5s and 4m at 2s