Question

write a formula for the length L of a rectangle given its perimeter P and its width w. justify your thinking

Answer 1

P= 2*L + ...?

find that expression (if you don't have it already) and solve it for L

Answer 2

is that the answer?

Answer 3

no. those are the steps you take to get the answer.

Answer 4

take them.

Answer 5

ok

Answer 6

can you be a little more specific

Answer 7

based on the drawing, can you find the perimeter in terms of L and W?

Answer 8

would it be P= 2*L +w?

Answer 9

trace the perimeter, how many L's and how many W's?

Answer 10

2 l and 2 w

Answer 11

yes, so P= ...?

Answer 12

4?

Answer 13

2L+2W

Answer 14

now solve P= 2L + 2W for L

Answer 15

but whats L

Answer 16

the length of any given rectangle

Answer 17

P= 2L + 2W is a general expression. You can use it to find the perimeter of ANY rectangle given the rectangle's length and width.