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3.1.3: Dividing Rational Expressions

Yuri will be making a glass window hanging with a metal frame for his art class. He is deciding which shape to use: a hexagon, a triangle, or a square. His window hanging must have all sides the same length.

1. If Yuri decides to use a hexagon (a 6-sided figure), what is the length of one side if the hexagon’s perimeter is 25 cm?

2. If he decides on a triangular shape, what is the length

of one side if the perimeter of the triangle measures

3. Yuri’s math teacher has a square frame with a perimeter of (8x + 12) cm. The teacher will give Yuri the frame if Yuri can tell him what expression represents the length of one side. What is the correct expression? 2

3.1.3: Dividing Rational Expressions

1. If Yuri decides to use a hexagon (a 6-sided figure), what is the length of one side if the hexagon’s perimeter is 25 cm?

• To determine the length of one side, divide the total perimeter, 25, by the number of sides, 6.

• With a total perimeter of 25 cm, the length of one side

of the hexagon is cm, or cm.

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3.1.3: Dividing Rational Expressions

2. If he decides on a triangular shape, what is the length

of one side if the perimeter of the triangle measures

• To determine the length of one side, divide the total

perimeter, , by the number of sides, 3.

• Recall that, when dividing fractions, you must

multiply by the reciprocal of the divisor; in this case,

the reciprocal of 3 is .4

3.1.3: Dividing Rational Expressions

• The length of one side of the triangle is m.

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3.1.3: Dividing Rational Expressions

3. Yuri’s math teacher has a square frame with a perimeter of (8x + 12) cm. The teacher will give Yuri the frame if Yuri can tell him what expression represents the length of one side. What is the correct expression?• Each of the four sides of a square is the same

length. To find the length of one side, we need to divide the perimeter by 4.

• The length of one side of the square is (2x + 3) cm.

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3.1.3: Dividing Rational Expressions