Osvaldo’s teacher asked him to write an equivalent equation for length, l, in terms of perimeter, p, and width, w. He wrote: p =

Question

3 years ago

13

Osvaldo’s teacher asked him to write an equivalent equation for length, l, in terms of perimeter, p, and width, w. He wrote: p =

2 l + 2 w His steps to solve were:1. Subtract 2 w. p minus 2 w = 2 l. 2. Multiply by 2. 2 (p minus 2 w) = l. His equivalent equation was l = 2 (p minus 2 w). Analyze Osvaldo’s work to determine where he made an error and what his error was. In step 1, he had to add 2w to both sides. In step 1, he had to divide both sides by 2w . In step 2, he had to divide both sides by 2. In step 2, he had to subtract 2 from both sides.

Mathematics