Answer: y = 7.5
Step-by-step explanation:
Suppose that y varies directly with x
That is, y∝x
Convert y∝x to a full equation by introducing a constant k to the right hand side.
Therefore, y = kx
Given that y = 10 and x = 20
Substitute y and x in the equation above. We have;
10 = k(20)
10 = 20k
20k = 10
k = 10/20
k = 0.5
Since k = 0.5, the equation y = kx becomes y = 0.5x
Now, to find y if x = 15, substitute x in equation y = 0.5x
Therefore, y = 0.5(15)
y = 7.5
Answer:
The cubic polynomial is: x³ - x² - 6x.
Step-by-step explanation:
Given the degree and the roots of the polynomial we can find it.
An n - degree polynomial has n roots.
Here, given that the degree of the polynomial is 3 and three roots are given. Also, if (x - a) is a factor of a polynomial then x = a is a root of the polynomial. The converse is also true.
Since, the roots of the polynomial are given to -2, 0, 3 then it should have had the following factors.
(x + 2)(x - 0)(x - 3) = 0
Multiplying them we get:
⇒
which is the required cubic polynomial.
Hence, the answer.
