Answer:
Translate the circles so they share a common center point, and dilate circle Y by a scale factor of 3.
Step-by-step explanation:
13. Pick a point and see which formula works.
Ay = -4, A'y = 7. Only the formula of selection D makes that translation.
14. Use the compound interest formula A = P*(1 +r/n)^(nt).
..1500*1.015^80 = 4935.99, matching selection C
15. The lid has a perimeter of 90", so the area of the sides is
.. 90" * 24" = 2160 in^2
The area of the lid is
.. 30" * 15" = 450 in^2
The gray area is (2160 -450) in^2 = 1710 in^2 larger, corresponding to selection C.
16. The only formula that maps (7, -1) to (21, -3) is that of selection D.
_____
The middle two problems are the only ones that require you to have prior knowledge. The others could be answered simply by seeing if the answers work.
Answer:
15
Step-by-step explanation:
70÷14=5
5×3=15
So the ratio would be 70:15 which can be simplified to 14:3
If y varies directly as the square of x, that means that y=k*x^2. Plugging y=100 and x=5 into it, we get 100=k*5^2=k*25. Dividing by both sides, we get k=100/25=4. Going back to the original equation, we now know that y=4*x^2. Plugging 9=x in, we get 4*9^2=4*81=324=y