**Princeton Review**

If 2a + 3b = 7, what is the value of b?

1) a − b = − 4

2) 4a = 14 − 6b

OA A

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**A**

**B**

**C**

**D**

**E**

Key property: If we have a system of 2 different linear equations with two variables, then we can solve that system for each variable

Since this linear equation is different from the given linear equation (2a + 3b = 7), we have a system of two different linear equations with two variables, which means we COULD solve that system for a and b (although we would never waste valuable time on test day doing so)

Since we could answer the target question with certainty, statement 1 is SUFFICIENT

This equation seems similar to the given equation (2a + 3b = 7). So let's investigate further....

Take: 4a = 14 − 6b

Divide both sides by 2 to get: 2a = 7 - 3b

Add 3b to both sides to get: 2a + 3b + 7

Since statement 2 provides us with an equation that is equivalent to the given equation (2a + 3b = 7), we DON'T have a system of two different linear equations.

As such, we can't solve that system for a and b.

Since we can’t answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer: A

Cheers,

Brent