(-9x²-2x) - (-9x²-3x) = (-9x²-2x) +(9x²+3x) = -9x²-2x+9x²+3x = (-9x²+9x²)+(-2x+3x) = x
Answer:
the answer is in fact 7/2
It is given in the question that
Anna buys 12 pens and 20 pencils for a total cost of $16. One pen costs $0.40 more than a pencil.
Let the cost of pencil is $ x .
Therefore cost of pen is

According to the question

Distributing 12 and combining like terms, we will get

Therefore cost of pencil is $0.35 and cost of pen is

<u>27 = 6x + 4y </u>= 1 7/20 = 3 4/5<u>
</u>20 = 2x + 5y<u>
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