Question

Number 13 I don’t get it

Answer 1

Answer:  1/2  (choice A)

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Explanation:

The two equations given to us are

• ab = 3
• ab^2 = 18

Divide the second equation over the first equation and that would lead to b = 6

Notice how the 'a' terms divide to 1 and go away, i.e. cancel out.

The b terms divide to (b^2)/b = b

The right hand side values divide to 18/3 = 6

So that's how we end up with b = 6

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Now if b = 6, then we can say,

ab = 3

a*6 = 3

a = 3/6

a = 1/2

Or we could say

ab^2 = 18

a*6^2 = 18

a*36 = 18

a = 18/36

a = 1/2