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
---------------------
20Q = 380
so
Q = 19
There are 19 quarters.
And since there are 51 coins in all, 51-19 = 32 nickels.
Answer:
w= -9/8
Step-by-step explanation:
-1/3w -3/5 = 1/5w
+1/3w +1/3 w
-3/5=1/5w+1/3w
Make common denominators to combine like terms of the right
-3/5=1/5w+1/3w
*3 *5
-3/5=3/15w+5/15w
-3/5=8/15w
multiply both sides by the reciprocal of 8/15 which is 15/8
-3/5*15/8=8/15w*15/8
*
----> cross reduce 5 in the denominator becomes 1 and 15 in the numerator becomes 3
*
-----> now multiply across
w= -9/8
Answer: 
Step-by-step explanation:
GCF = Greatest common factor.
For example: 6 is the GCF of 12 and 18.
The given expression: 
It can be written as
Taking out common factor 
, we get
![5y(x^2-6xy-7y^2)\\\\ =5y(x^2+xy-7xy-7y^2)\ \ [\because-6xy=xy-7xy]\\\\=5y(x(x+y)-7y(x+y))\\\\= 5y((x+y)(x-7y))\\\\=5y(x+y)(x-7y)](https://tex.z-dn.net/?f=5y%28x%5E2-6xy-7y%5E2%29%5C%5C%5C%5C%20%3D5y%28x%5E2%2Bxy-7xy-7y%5E2%29%5C%20%20%5C%20%5B%5Cbecause-6xy%3Dxy-7xy%5D%5C%5C%5C%5C%3D5y%28x%28x%2By%29-7y%28x%2By%29%29%5C%5C%5C%5C%3D%205y%28%28x%2By%29%28x-7y%29%29%5C%5C%5C%5C%3D5y%28x%2By%29%28x-7y%29)
Hence,
Answer:
=
10
−
2
7
-
3
Step-by-step explanation:
