Answer: B = 10A + 8
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Step-by-step explanation:
This is something you would do through trial and error to check each answer choice
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We can cross off A = 10B since
A = 10B = 10*(6,007,058) = 60,070,580
but that's not what A is actually equal to (it should be 600,705)
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We can also cross off A = 100B + 58 because,
A = 100B + 58
A = 100*(6,007,058) + 58
A = 600,705,800 + 58
A = 600,705,858
But that doesn't match with A = 600,705 either
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Now let's try the third equation
B = 10A + 8
B = 10(600,705) + 8
B = 6,007,050 + 8
B = 6,007,058
That matches with what your teacher gave you. So this confirms we have the correct equation.
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I'll let you check the remaining two. You should find that they don't work out.