text: x=time to run at 8.5 m/s\n99-x=time to run at 8.0 m/s\n1st lap length = 8.5x\n2nd lap length= 8(99-x)\n\nsince the length are the same\n8.5x=8(99-x)\n8.5x=792-8x     add 8x to both sides\n+8x        +8x\n16.5x=792         divide by 16.5 on both sides\nx=48\n99-x=51\n\nHe runs the first lap in 48 sec, and the second lap in 51 sec