If we let Q be the number of quarters and N be number of nickels, this is the formula we would use:
[1] 25Q + 5N = 635 (using cents instead of dollars)
We also know something about Q and N.
[2] Q + N = 51
So multiply both sides of the second equation by 5. The reason we do this is because we're going to need to cancel out one of the variables (either Q or N) to solve for the other one. If we multiply times 5, we'll have 5N in both equations.
5Q + 5N = 255
Now we have two equations, and the second one can be subtracted from the first.
25Q + 5N = 635
-(5Q + 5N) = -255
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20Q = 380
so
Q = 19
There are 19 quarters.
And since there are 51 coins in all, 51-19 = 32 nickels.
Answer:
Step-by-step explanation:
(-8a - 1)- (-7a + 5) = -8a - 1 - 7a*(-1) + 5*(-1) { (-1) is disturbed to all the terms in (-7a +5)}
= -8a - 1 + 7a - 5
= -8a + 7a -1 - 5 {Combine like terms}
= -a - 6
2850*24/(4*24+18)
The light bulb consumes 600 watt-hours per day.
Answer: The answer is 3^12.
Step-by-step explanation: