Step 5 Set up the operations or tasks

This is where all the previous steps should be coming together. You have the question in mind and a picture of what s happening. You have an estimate or guess of how the answer should come out. You have variable expressions representing the distances traveled. Now you need to set up a process or equation. Sometimes the process is no more than multiplying a number by 2 or 3. That s the best-case scenario. But it s much more fun when you set up an equation to be solved. 

The previous work on this problem suggests an equation. You have two different distances represented by expressions involving a y. Write an equation and solve fory. What equation Why Pythagoras s, of course  

In a right triangle whose shorter sides are a and b in length and whose longest side is c long, the following is always true a2 + b2 = c2. 

The distances that Shirley and Shelly walked are the a and b of a right triangle. The distance that they re apart, 17 miles, is the c value. Substituting into the Pythagorean theorem, the equation a2 + b2 = c2 becomes (y)2 + (2y - l)2 =172. 

Mike had just finished pouring and smoothing out a new concrete sidewalk when he noticed that someone had written in the numbers 111 111 999 in the walk. He should have been angry or disgusted, but instead, he made a puzzle 

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