Answer:
x =4 ,y =4 and z =0 is the solution.
Step-by-step explanation:
We shall solve the equations using elimination method
In equation 2 and 3 we can see that coefficient of z in both equations are same with opposite sides , adding equations (2) and (3)
3y+5z = 12
y -5z = 4 adding the equations
___________
4y = 16
dividing both sides by 4
y =
y = 4
Plugging the value of y in equation 2 or equation 3 ,we get
3(4) +5z = 12
12+5z = 12
5z = 12-12 or 5z =0 gives z =0
plugging y =4 and z =0 in equation 1
2x+3(4)+ 0 = 20
2x+12 = 20
2x =20-12
2x = 8
x = 8 divided by 2 gives
x =4
therefore solution of the system is given by
x=4 , y =4 and z =0
Letter D. because any opposite number of a negative has to be a positive!
Answer:
Step-by-step explanation:
Let's call hens h and ducks d. The first algebraic equation says that 6 hens (6h) plus (+) 1 duck (1d) cost (=) 40.
The second algebraic equations says that 4 hens (4h) plus (+) 3 ducks (3d) cost (=) 36.
The system is
6h + 1d = 40
4h + 3d = 36
The best way to go about this is to solve it by substitution since we have a 1d in the first equation. We will solve that equation for d since that makes the most sense algebraically. Doing that,
1d = 40 - 6h.
Now that we know what d equals, we can sub it into the second equation where we see a d. In order,
4h + 3d = 36 becomes
4h + 3(40 - 6h) = 36 and then simplify. By substituting into the second equation we eliminated one of the variables. You can only have 1 unknown in a single equation, and now we do!
4h + 120 - 18h = 36 and
-14h = -84 so
h = 6.
That means that each hen costs $6. Since the cost of a duck is found in the bold print equation above, we will sub in a 6 for h to solve for d:
1d = 40 - 6(6) and
d = 40 - 36 so
d = 4.
That means that each duck costs $4.
The total cost for one can is: $25.41.
__________________________________________________
Let us assume that we want to know the total cost of ONE CAN.
_____________________________________________
To calculate our answer:
_______________________________
$ 23.97 + [ (6/100) * 23.97)] = Our answer, in dollars.
__________________________________________
Note: "6%" = 6/100 = 0.06
_______________________
Rewrite as:
____________
$ 23.97 + [ (6/100) * 23.97)] = our answer, in dollars;
_____________________________________________
$ 23.97 + (0.06 * 23.97)
= $ 23.97 + 1.4382
= $ 25.4082 ; Round to decimal places, to get:
<span>→ $ 25.41
</span>__________________________________________
In your change cup you have 28 coins. All of which are nickels and quarters. Together they add up to $4. How many coins do you have of each.
