Me

which expression represents the value of x?

Step-by-step explanation:

By the Pythagorean theorem, triangle BCD has

and triangle ABD has

.

Substituting the first equation into the second equation for gives the equation

Now triangle ABC has

Expanding out the left side, .

Now substitute the equation from before, , into the new equation.

We work to isolate by adding to both sides of equation and subtracting from both sides.

Divide both sides by 2 and you get

Assume that x is positive and square root both sides to get the final result of

d

step-by-step explanation:

d

the answer is: d) o, f, and kr.

atomic radius of bromine (br) is 114 pm.

atomic radius of oxygen (o) is 73 pm.

atomic radius of fluorine (f) is 72 pm.

atomic radius of krypron (kr) is 112 pm.

the atomic radius of a chemical element is a measure of the size of its atom.

the atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.

the atomic radius decreases across the periods because an increasing number of protons, because greater attraction between the protons and electrons.