What does descartes rule of signs say about number of positive real roots and negative real roots of p(x) x^3+6x^2+9x+5

There are no positive roots

Step-by-step explanation:

The Descartes' rule posits that, given a polynomial with real coefficients ordered, the number of positive roots is equal to the amount of sign-changes OR to such amount minus a number multiple of 2. In you polynomial  P(x)=x^3+6x^2+9x+5 you have NO sign-changes, as every coefficient is positive. So, we can confirm that, if the polynomial has real roots, none of these are positive. As 0 can'y be a root of P(x) (replace x=0 and confirm), if there is some root, it will be a negative root. However, the rule can't confirm that there are roots.

answer

d. 10

explanation

the distance from point y to wx is the height of the triangle.

using pythagoras theorem,

group similar terms to get,

this implies that,

take positive square root of both sides to get,

this implies that,