There are 13 protons because the atomic number (the number in the top left corner) represents the number of protons. Then, to find the number of neutrons, you take the number of protons and subtract it from the atomic mass (the number on the bottom) when it is rounded. The number of electrons is the same as the protons when the atom is neutral
Answer:
24hours divided by 2 is 12
Step-by-step explanation:
Answer:
x=-2, y=-2. (-2, -2).
Step-by-step explanation:
2x-5y=6
-2x+10y=-16
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5y=-10
y=-10/5=-2
2x-5(-2)=6
2x+10=6
2x=6-10
2x=-4
x=-4/2=-2
Answer:
# yellow = 20
# blue = 23
# red = 5
Step-by-step explanation:
let 'r' = # red marbles
let '4r' = # yellow marbles
let '3+4r' = # blue marbles
r + 4r + 3 + 4r = 48
9r + 3 = 48
9r = 45
r = 5
red = 5
yellow = 4(5) = 20
blue = 3+4(5) = 23
