3x+6y=27 -> x+2y=9 -> z=11-(x+2y)=2 -> z+5=x+2y-2 -> C

Explanation

This question may at first look difficult, as there are three variables and only two equations.

However, notice that the top equation can be divided by 3, yielding x + 2y = 9. This can be plugged into the second equation:

(x + 2y) + z = 11

(9) + z = 11

z = 2

Quantity A is thus 2 + 5 = 7. For Quantity B, remember that x + 2y = 9. Thus, Quantity B is 9 – 2 = 7.

The two quantities are equal.

\(3(x +2y)= 27\)
or, \(x+2y = 9\)

Qyt B = \(x+2y - 2\)
or, Qty B = \(9-2 = 7\)

Qty A = \(z + 5\)
we have, \(x+2y + z = 11\)
or, \(9 +z = 11\)
therefore \(z = 2\)
Hence Qty A = \(2 + 5 = 7\)

Notice that we can simplify of the first given equation, 3x + 6y = 27, by dividing both sides by 3 to get: x + 2y = 9

So are two different equations now look like this:
x + 2y + z = 11
x + 2y = 9

Subtract the bottom equation from the top equation to get: (x + 2y + z) - (x + 2y) = 11 - 9
Simplify: z = 2

Now we can take the given equation x + 2y + z = 11 and replace z to get: x + 2y + 2 = 11
Subtract 2 from both sides of the equation to get: x + 2y = 9

We now have:
QUANTITY A: z + 5 = 2 + 5 = 7
QUANTITY B: x + 2y - 2 = (x + 2y) - 2 = 9 - 2 = 7

Answer: C

Cheers,
Brent

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