Hi I don’t really understand can you explain a little bit please
Answer:

Step-by-step explanation:
we know that

Is the equation of a vertical parabola written in vertex form
where
(h,k) is the vertex
a is the leading coefficient
In this problem we have
The vertex is the point (-1,4)
so

substitute

Find the value of a
we have the ordered pair (0,3)
substitute the value of x and the value of y in the quadratic equation and solve for a


therefore

The cost of each stone sphere is $ 36.81
<em><u>Solution:</u></em>
Given that,
An architect plans to buy 5 stone spheres and 3 stone cylinders
For the same amount, she can buy 2 stone spheres and 6 stone cylinders
Let "x" be that same amount
Let "a" be the cost of each stone sphere
Cost of each stone cylinder = $ 36.81
Therefore,
x = 5 stone spheres and 3 stone cylinders
x = 5a + 3(36.81)
Similarly,
x = 2 stone spheres and 6 stone cylinders
x = 2a + 6(36.81)
Equate both,

Thus cost of each stone sphere is $ 36.81