Answer:
Option 4 is correct.
The equation
is equivalent to 
Step-by-step explanation:'
Given equation: 
First group the terms with x and those with y;

Next, we complete the squares.
We can do this by adding a third term such that the x terms and the y terms are perfect squares.
For this we must either add the same value on the other side of the equation or subtract the same value on the same side so that the equality is maintained.
⇒
or



Add 360 on both sides we get;

Simplify:

Therefore, the given equation is equivalent to 
Answer:
10 cm
Step-by-step explanation:
Given:
No. of small spherical bulb = 1,000
radius (r) of smaller bulbs = 1 cm
Required:
radius of the bigger bulb
SOLUTION:
The following equation represents the relationship of the volume of the smaller and bigger bulb,

Where,
= volume of bigger bulb
= volume of smaller bulb
1,000 is the number of smaller bulbs melted to form the bigger bulb.
Volume of a sphere is given as, ⁴/3πr³
Therefore:
= ⁴/3*π*r³ = 4πr³/3
= ⁴/3*πr³ = ⁴/3*π*(1)³ = ⁴/3π*1 = 4π/3
Plug the above values into the equation below:





(12pie cancels 12 pie)
(taking the cube root of each side)
Radius of the bigger bulb = 10 cm
Answer: The ball will hit the ground 4 seconds after being thrown.
Step-by-step explanation:
By definition, the ball hits the grounds when the height is zero.
Then, knowing that the Quadratic function that models that situation is:

You can make it equal to zero:

Now you can use the Quadratic formula:

In this case you can identify that:

Therefore, knowing these values, you can substitute them into the Quadratic formula and then evaluate, in order to find the solution:

Choose the positive solution.
Then, the ball will hit the ground 4 seconds after being thrown.