Let's simplify each expression to determine which are equivalent.
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Expression 1: \(-0.4b + (6b - 5.9a)\) Simplifying this gives: \[ -0.4b + 6b - 5.9a = (6b - 0.4b) - 5.9a = 5.6b - 5.9a \]
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Expression 2: \((2.5a + 1.6b) + (3.4a + 4b)\) Simplifying this gives: \[ 2.5a + 1.6b + 3.4a + 4b = (2.5a + 3.4a) + (1.6b + 4b) = 5.9a + 5.6b \]
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Expression 3: \((-3.9b + a) + (-1.7b + 4.9a)\) Simplifying this gives: \[ -3.9b + a - 1.7b + 4.9a = (-3.9b - 1.7b) + (a + 4.9a) = -5.6b + 5.9a \]
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Expression 4: \((3.4a - 1.7b) + (2.5a - 3.9b)\) Simplifying this gives: \[ 3.4a - 1.7b + 2.5a - 3.9b = (3.4a + 2.5a) + (-1.7b - 3.9b) = 5.9a - 5.6b \]
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Expression 5: \(5.9a - 5.6b\) This expression is already simplified.
Now let's summarize the simplified forms:
- Expression 1 simplifies to \(5.6b - 5.9a\)
- Expression 2 simplifies to \(5.9a + 5.6b\)
- Expression 3 simplifies to \(-5.6b + 5.9a\)
- Expression 4 simplifies to \(5.9a - 5.6b\)
- Expression 5 is \(5.9a - 5.6b\)
We can see that:
- Expression 4 and Expression 5 are equivalent (both simplify to \(5.9a - 5.6b\)).
- Expression 3 simplifies to \(-5.6b + 5.9a\), which is equivalent to Expression 4 (since they are rearrangements).
Therefore, the equivalent expressions are:
- Expression 3
- Expression 4
- Expression 5
Final equivalent expressions are:
- \(3. (−3.9b+a)+(−1.7b+4.9a)\)
- \(4. (3.4a−1.7b)+(2.5a−3.9b)\)
- \(5. 5.9a−5.6b\)
So the answer is: Expressions 3, 4, and 5.