9514 1404 393
Answer:
(x, y) = (4, 2)
Step-by-step explanation:
The triangles are similar by AA similarity, so the corresponding angles are congruent.
5x -y = 18 . . . . . . unmarked angles are congruent
18 +(3x+y) +148 = 180 . . . . . sum of angles in a triangle is 180°
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After subtracting 166 from both sides, the second equation simplifies to ...
3x +y = 14
Adding this to the first equation gives ...
8x = 32
x = 4 . . . . . . divide by 8
Then substituting for x in the first equation gives ...
5(4) -y = 18
20 -18 = y = 2
The values of the variables are x = 4, y = 2.
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The angle marked with a double mark is 14°, given by the simplified second equation.