Note that the 2nd equation can be re-written as y=8x-10. According to the second equation, y=x^2+12x+30. Equate these two equations to eliminate y:
8x-10 = x^2+12x+30
Group all terms together on the right side. To do this, add -8x+10 to both sides. Then 0 = x^2 +4x +40. You must now solve this quadratic equation for x, if possible. I found that this equation has NO REAL SOLUTIONS, so we must conclude that the given system of equations has NO REAL SOLUTIONS.
If you have a graphing calculator, please graph 8x-10 and x^2+12x+30 on the same screen. You will see two separate graphs that do NOT intersect. This is another way in which to see / conclude that there is NO REAL SOLUTION to this system of equations.
Step-by-step explanation: In 4 hours, you hike 10 miles. Divide 10 miles by 4 hours to get miles per hour, which is what you want to solve for in this problem. 10 divided by 4 is 2.5, which means you can hike 1 mile in 2.5 hours.