7 times 8 is 56
9 times 10 is 90
Answer:
The diameter decreases at a rate of 0.143cm/min when it is of 10 cm.
Step-by-step explanation:
Surface area of an snowball:
An snowball has spherical format. The surface area of an sphere is given by:

In which d is the diameter of the sphere.
In this question:
We need to differentiate S implicitly in function of time. So

Surface area decreases at a rate of 9 cm2/min
This means that 
At which the diameter decreases when the diameter is 10 cm?
This is
when
. So




Area in cm², so diameter in cm.
The diameter decreases at a rate of 0.143cm/min when it is of 10 cm.
The two marked angles are complementary angles. This means that the angles are equal.
Hence, X + 1 = 2X - 3.
By rearranging, X = 4.
Answer:
The same ratio indicates that there is a proportional relationship between y and x.
Step-by-step explanation:
We know when y varies directly with x, the equation is
y ∝ x


Here,
k is the constant of proportionality.
The ratio y/x indicates that k is a constant of proportionality.
Thus, the same ratio indicates that there is a proportional relationship between y and x.
When x increases, y increases, and when y decreases, x also decreases.
Answer:
Fourth option y = x²
Step-by-step explanation:
It is clear from the graph that parabola passes through origin, which is it's vertex and line of symmetry is y-axis.
So the equation of the parabola will be y = (x - 0)² + 0
This equation of the parabola is in the vertex form [ y = (x - h)² + k]
Therefore, equation of the parabola will be y = x²
This equation is true for the given values of x and y in the table.
For (-2, 4) ⇒ 4 = (-2)²
For (-1, 1) ⇒ 1 = (-1)²
Fourth option y = x² is the answer.