Answer: " Yes; Kim is correct."
Explanation: [refer to the end of this "answer"].
Note: Any "triangle" has 3 sides and 3 angles.
An isosceles triangle has 2 (angles) with the exact same measurements.
We are given the following information:
We have an isosceles angle:
 with one of the angles = 48°
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Does this mean that one of the angles must be: 66 ° ? 
If so; then: either:
 48 + 66 + 48 = 180 ?
or: 48 + 66 + 66 = 180 ?
 1) First: Start with 48 + 66 + 48 ≟ 180 ? 
 (48 + 66 + 48) ≟ 180 ? ; 162 ≟ 180? No; " 162 < 180 " .
 
2) Second: Try: "48 + 66 + 66 = 180 " .
 (48 + 66 + 66) ≟ 180 ? ; 180 ≟ 180 ? ; Yes! "180 = 180". 
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So: Kim is correct; because isosceles triangles must have angles with 2 (two) equal measurements. Note that all triangles have angles that add up to 180° . 
 So: As shown above: 
  If one angle of the triangle is 48°; then: **each** of the other angle measurements must be 66°.
 So: Yes; Kim is correct when he says that one of the other angles must be 66°.
 (48 + 66 + 48) ≟ 180 ? ; 162 ≟. 180? No; " 162 < 180 " .
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Hope this is helpful to you! Wishing you well!
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