Answer:
x = 5, Y = 4
Step-by-step explanation:
3x -2y = 7
-3x +9y = 21. (multiple the whole thing by 3 to get the xs to cancel)
7y = 28
y = 4
substitute y to find x
3x - 2(4) = 7
3x -8 = 7
3x = 15
x = 5
I believe the correct answer from the choices listed above is the second option. If an oxygen atom has 8 protons and 10 neutrons in its nucleus, then its atomic number would be 8. The atomic number is <span>the number of protons in the nucleus of an atom. Hope this answers the question.</span>
Answer:
24
Step-by-step explanation:
Using Pythagoras theorem,
a^2 = b^2 + c^2
40^2 = 32^2 + c^2
1600 = 1024 + c^2
1600 - 1024 = c^2
576 = c^2
square root of 576 = c
24 = c
30 because 0.3 * 100 = 30
