Answer:
x = 9 cm
y = 4 cm
Step-by-step explanation:
The angle markings tell you the three angles of one triangle are equal to the three angles of the other triangle. That means the triangles are "similar", and the lengths of corresponding sides have the same ratio.
The bottom sides, between the angles with 1 mark and 3 marks, are shown as 3 cm in the green triangle and 6 cm in the blue triangle. This tells you all of the the green triangle dimensions are half those of the corresponding dimensions in the blue triangle:
x = (18 cm)/2 = 9 cm
It also tells you the blue triangle dimensions are 2 times those of the green triangle:
y = 2(2 cm) = 4 cm
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Additional comments
Corresponding sides having the same ratio means they are proportional (and vice versa). This can be expressed in equation form as ...
y/(2 cm) = (18 cm)/x = (6 cm)/(3 cm)
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You may want to discuss this problem with your teacher. The side lengths shown in the figure do not form a triangle. The two short sides are too short to connect to the ends of the long side. The figure is impossible.
