Question

Look at the given triangles.

triangles

The blue triangle is a right triangle. The vertical leg is labeled with the expression 4 x plus 2. The horizontal leg is labeled with the expression 5 x minus 4. The hypotenuse is labeled with the expression 7 x plus 7.

The red triangle is a right triangle. The vertical leg is labeled with the expression x plus 3. The horizontal leg is labeled with the expression x plus 7. The hypotenuse is labeled with the expression 2 x minus 5.


a. Write an expression in simplest form for the perimeter of each triangle.

b. Write another expression in simplest form that shows the difference between the perimeter of the larger triangle and the perimeter of the smaller triangle.

c. Find the perimeter for each triangle when x = 3

Answer 1

Explanation:

Blue triangle

a = 4x + 2

b = 5x - 4

c = 7x + 7

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perimeter = a + b + c

4x + 2 + 5x - 4 + 7x + 7

16x + 5

Blue triangle Perimeter = 16x + 5

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Red triangle

a = x + 3

b = x + 7

c = 2x - 5

perimeter = a + b + c

x + 3 + x + 7 + 2x - 5

4x + 5

Red triangle Perimeter = 4x + 5

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The difference between

Larger triangle -> Blue

Smaller triangle -> Red

(16x + 5) - (4x + 5) = 12x

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Perimeter when x = 3

Blue triangle Perimeter = 16x + 5

16*3 + 5 = 53

Red triangle Perimeter = 4x + 5

4*3 + 5 = 17