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3 years ago

Hoang has worked as a nurse at Springfield General Hospital for 7 years longer than her friend Bill. Two years ago, she had been

Mathematics

1 answer:

Evgesh-ka [11]3 years ago

3 0

Answer:

$Bill\to 9\ years$

$H \to 16\ years$

Step-by-step explanation:

Let

$H \to Hoang$

$B \to Bill$

Currently:

$H = B + 7$

Two years ago

$H - 2 = 2 * (B -2)$

Required

H and B

We have:

$H - 2 = 2 * (B -2)$

Open bracket

$H -2 =2B - 4$

Add 2 to both sides

$H -2+2 =2B - 4+2$

$H =2B -2$

Substitute $H = B + 7$

$B + 7 =2B -2$

Collect like terms

$2B - B =7+2$

$B = 9$

Substitute $B = 9$ in $H = B + 7$

$H = B + 7$

$H = 9 + 7$

$H = 16$

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