Answer:
(x, y) = (-3, -6)
Step-by-step explanation:
The second equation can be used to write an expression for y:
... -5x -21 = y . . . . . . . add y-21 to both sides
This expression can be substituted for y in the first equation:
... 6 = -4x +(-5x -21)
... 27 = -9x . . . . . add 21, collect terms
... -3 = x . . . . . . . divide by -9
Using this value of x in the expression for y, we find ...
... -5(-3) -21 = y = -6
The solution is x = -3, y = -6.
Answer:
8.2
Step-by-step explanation:
We have been given that the ratio of hydrogen to oxygen atoms in water molecules is 2 to 1.
We can represent this information as:
Let x be amount of moles of hydrogen atoms in water beaker. The proportion of hydrogen and oxygen moles will be same in water beaker.
Upon substituting our values in above proportion we will get,
Therefore, the moles of hydrogen atoms in water beaker will be 8.2.