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5 votes
If x - 15 = 30, what is the value of 2(x + 5)?

User Ecantu
by
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1 Answer

16 votes
16 votes

Answer:

100

Explanation:

When ...

x -15 = 30

we can find the value of x by adding 15 to both sides of the equation:

x = 45

To find the value of 2(x +5), we can substitute 45 for x:

2(x +5) = 2(45 +5) = 2(50)

2(x +5) = 100

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Alternate solution

Adding 20 to both sides of the first equation gives the value of x+5.

(x -15) +20 = (30) +20

x +5 = 50

The second expression is double this value:

2(x +5) = 2(50) = 100

User Mortennobel
by
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