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Suppose you have 30 CDs. You know that you have 11 more CDs than your friend. How do you write and solve an equation to find the number of CDs your friend has?

Answer 1

Hazel Anglin

A simple equation would be: #x+11=30#.

My friend, therefore, has #19# CDs.

We consider the number of CDs my friend has as #x#.

Since we know that I have #30# CDs which is #11# more than what my friend has, the equation can be simply written as:

#x+11=30#

Subtracting #11# from both sides, we get:

#x=30-11#

#:. x=19#

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Answer 2

Jace Anderson

Let x represent the number of CDs your friend has.

Equation: x + 11 = 30

Solution: x + 11 = 30 x = 30 - 11 x = 19

Your friend has 19 CDs.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.