I solved with addition elimination, and matrices elimination and received the same answer. (0,0,-3) I hope that helps.
Answer:
<em>8 C sometimes</em>
<em>9 64x^8 y^11</em>
<em>10 c 1.28r^2/ t^9</em>
Step-by-step explanation:
<u>Algebraic Operations
</u>
Some basic rules must be fresh in our minds when trying to simplify complex algebraic expressions. For example, the power rule respect to the product or quotient:



Let's face the questions at hand
8. A number is raised to a negative exponent is negative?
Following the expressions recalled above, let's pick the expression

This is a negative power resulting in a positive number
Now we pick

This time, the negative power leads to a negative result, so it doesn't matter the sign of exponent to determine the sign of the result
<em>Answer: C sometimes
</em>
9 simplify(4xy^2)^3(xy)^5



10 simplify(2t^-3)^3(0.4r)^2




11,000 or 10,000 or 11,200 or 11,230
Your answer is going to be Letter B
If x is the amount that Tanya paid for each item, then Tony's items would be x-2.25. So:
3x=4(x-2.25)
3x=4x-9
x=9
x-2.25=6.75
Tanya spent $9 on each item; Tony spent $6.75 on each of his items