7x+5y=-24 (1)
4x+y=42 (2)
multiply equation (2) by 5 to get
20x+5y=210 (3)
then calculate (3)-(2) which gives you
13x=234 hence x=18
then substitute for x in either equation to get y=-30
False because you can only use the Pyth. Theorem on right triangles which may not necessarily be ALL similar triangles.
Answer:

Step-by-step explanation:
Given that,
The dimensions of an aquarium are 61 cm long, 30.5 cm wide, and 30.5 cm high.
The tank is filled to 80% capacity with water.
We need to find the water needed for this tank.
The volume of cuboid is given by :

As it is filled to 80% capacity, so,

So,
of water is needed for this tank.
18 divided by 30 is 0.6. So I would say that B, or 0.6, is the correct answer.