Answer:
8. A'(-1/2, 1), B'(0, 0), C'(1, 1 1/2)
10. 20°, 60°, 100°
Explanation:
8. Point B is at the origin, the center of dilation, so its coordinates remain unchanged. The coordinates of A and C are each multiplied by the scale factor, 1/2.
A' = (1/2)A = (1/2)(-1, 2) = (-1/2, 1)
C' = (1/2)C = (1/2)(2, 3) = (1, 3/2)
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10. The total number of ratio units is 1+3+5 = 9. The total of angle measures in any triangle is 180°. So, each of the "ratio units" must stand for 180°/9 = 20°. Then the angles are ...
1 · 20° = 20°
3 · 20° = 60°
5 · 20° = 100°