X^2-4x+4=9 solve the equation using square roots

X=5 or X=-1

Step-by-step explanation:

Use the method complete the square.

1. Subtract 4 from both sides.

X^2-4x+4-4=9-4

Find what value added to both sides of the equation will make the equation on the left a perfect square trinomial.

(B/2)^2

-4/2=-2   (-2)^2 = 4

2.Add 4 to both sides.

X^2-4x + 4= 5+4

3.Factor

(x-2)^2=9

Solve for X

x-2= +or- 3

x=5 or x=-1

42.4

step-by-step explanation:

convert to decimal

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.