Respuesta :

9514 1404 393

Answer:

  1. x = 7
  2. x = 1.2

Step-by-step explanation:

1. Sides with the same mark are congruent:

  7x -4 = 31

  7x = 35 . . . . . . add 4

  x = 5 . . . . . . . . divide by 7

Similarly, ...

  4y +8 = 24 . . . sides with 3 hash marks are the same length

  y +2 = 6 . . . . . divide by 4

  y = 4 . . . . . . . . subtract 2

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2. The (corresponding) right angles at B and D are congruent, and the angle at A is congruent with itself. This means triangles ABC and ADE are similar by the AA theorem. (Your flow chart might be: (show 2 angles the same) → (claim AA similarity).)

Similar triangles have corresponding sides in the same ratio:

  x/3 = (x+4)/13

  13x = 3(x +4) . . . . . . multiply by 3×13

  10x = 12 . . . . . . . . . . subtract 3x

  x = 1.2 . . . . . . . . divide by 10