For problems like this you can move the y's on the bottem up top by fliping the sign of the exponent (in this case 7 to -7) and MULTIPLYING it with EVERYTHING on top, then because of properties of multplication you can add the exponents to combine them into one term (in this case add 3 and -7 to get -4)

If any of this does not make sense let me know and ill try to clarify better
Row D because if you plug in 10 for x you get 17 not 15z
Answer: $101.25
Step-by-step explanation:
Since we are given the information that one metre of ribbon costs $0.45 and that Tabitha buys 225 metres of ribbon, the amount that she will have to pay will be gotten by multiplying the cost of one meter of ribbon by the total meters that she bought. This will be:
= $0.45 × 225
= $101.25
Therefore, the cost is $101.25
A = w(2w + 3)
90 = 2w^2 + 3w
2w^2 +3w - 90 = 0
(w-6)(2w+15) = 0 (TRINOMIAL FACTORING)
w = 6 inch ( it can't be -15/2 because lengths can't be negative)
l = 2w + 3
= 15 inch