The area of the rectangle shown is 180 square centimeters (cm). Find its dimensions. Use the equation: L(L + 3) = 180. (You may want to distribute first.)
http://curriculum.kcdistancelearning.com/courses/ALG1x-HS-A06/b/Exams/7Exam/7Exam_q47.gif
18 cm x 10 cm
12 cm x 15 cm
9 cm x 20 cm
6 cm x 30 cm

Question

The area of the rectangle shown is 180 square centimeters (cm). Find its dimensions. Use the equation: L(L + 3) = 180. (You may want to distribute first.)
http://curriculum.kcdistancelearning.com/courses/ALG1x-HS-A06/b/Exams/7Exam/7Exam_q47.gif
  18 cm x 10 cm 
   12 cm x 15 cm 
   9 cm x 20 cm 
   6 cm x 30 cm

anonymous · Answer

@primeralph

terenzreignz · Answer

Interesting how all of these pairs have a product of 180 but only one of them has a difference of 3 in their dimensions... :3

mathstudent55 · Answer

You will have a quadratic equation to solve.

terenzreignz · Answer

Distribute first... why don't we do that? :D
$$\Large L^2 +3L = 180$$
and solve for L... somehow... :3

terenzreignz · Answer

We want zero on one side (the right-side, perhaps?)
So we subtract 180 from both sides, which gives us:
$$\Large L^2 + 3L - 180 = 0$$

primeralph · Answer

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