Answer:
a = 7
Step-by-step explanation:
3a - 6 = 8 + a
{(-3, -3),(-6, -7), (6,-3), (–9, 2)} {(8,–8), (-9,5), (9,-2), (-2,-8)}
{(-7, -3), (-6, -1), (-6,8), (6, -6)}
Note that 20 (an approximation for 205) less 4 (an approx. for 431) comes out to 16.
This tells us that the proper placement of the decimals is
20.50
- 4.31
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and this comes out to 16.19.