Andy wants to find the distance across a river. In order to find the distance CD, Andy stands at point D , directly across from point C , and walks 200 feet to the left, placing a marker at a point E. Andy continues walking another 300 feet to point A , and then follows the path to the left, walking until the markers at points E and C line up. Andy marks this location B and measures AB .

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step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

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13 - r - 1 + r

= 12 - r

c

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= - 8 - r + 2r - 4

= - 12 + r

d

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= 7r - - - 6r

[-   - = - - = - ]

= r -

114 plus 113 times 2 and 114 times 3

i want the details r