Linear equations by substitution
2x-3y=24
2x+y=4

x =  4    and         y = -5

Step-by-step explanation:

2x-3y=24  --------------------------------------------------(1)

2x+y=4 ------------------------------------------------------(2)

We are to solve using substitution method.

From equation (2),

2x + y = 4

subtract 2x from both-side of the equation

2x - 2x + y = 4 - 2x

y = 4 - 2x  ------------------------------------------------(3)

Substitute equation (3) in equation (1)

2x-3y=24

2x - 3(4 - 2x) = 24

2x - 12 + 6x = 24

8x - 12 = 24

Add 12 to both-side of the equation

8x - 12 + 12 = 24 + 12

8x = 36

Divide both-side of the equation by 8

8x/8 = 36/8

x = 9/2  =  4

Substitute x = 9/2 in equation (3) to get the value of y

y = 4 - 2x

   = 4 - 2()

   = 4 - 9

   = -5

y = -5

x =  4    and         y = -5

v = 1/3 a^2h

step-by-step explanation:

the volume is 1/3 a^2h.

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.