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The triangles are not similar. The 3 angles in a triangle must add to 180. The first triangle must have 51+x+37=180. Subtract 51 and 37 from both sides and x=92. The second triangle 51+90+y=180. Subtract 51 and 90 from both sides so y=39.
For similar triangles all 3 angles must have the same values. 51,37,92(first triangle's angles) is different from 51,39,90(second triangle's angles).
Thus, they are not similar.
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