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.
No change in area if sides of rectangle are equal.
Hope this helps.
Answer:
All of them are yes because you either subtract or add to put in the form of mx+b
F(-1)
replace all x with -1
f(-1)=-3(-1)^2+2(-1)-7
f(-1)=-3(1)-2-7
f(-1)=-3-9
f(-1)=-12
Answer:
{d,b}={4,3}
Step-by-step explanation:
[1] 11d + 17b = 95
[2] d + b = 7
Graphic Representation of the Equations :
17b + 11d = 95 b + d = 7
Solve by Substitution :
// Solve equation [2] for the variable b
[2] b = -d + 7
// Plug this in for variable b in equation [1]
[1] 11d + 17•(-d +7) = 95
[1] -6d = -24
// Solve equation [1] for the variable d
[1] 6d = 24
[1] d = 4
// By now we know this much :
d = 4
b = -d+7
// Use the d value to solve for b
b = -(4)+7 = 3
Solution :
{d,b} = {4,3}
