What must be the length of zy in order for zy to be tangent to circle x at point y? 14 units 15 units 16 units 17 units

answer:

15

step-by-step explanation:

answer: second option

step-by-step explanation:

remember the following theorem: "the tangent of a circle is perpendicular to the radius through the point of contact".

then, if the radius is perpendicular to the tangent, the angle formed measures 90° degrees. therefore, the triangle shown in the figure is a right triangle.

knowing this, you can appply the pythagorean theorem to calculate the lenght zy:

where "a" is the hypotenuse and "b" and "c" are the legs of the right triangle.

in this case:

then you need to substitute values:

and finally you must solve for zy:

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.

ok

step-by-step explanation: