First:
2x + 2z = 4
2(x+z)=4
x+z=4/2
x=2-z
-x - y - z= -8
-(2-z)-y-z= -8 replace x
-2+z-y-z= -8 (cancel z)
-2-y= -8
6 = y
Then:
-4x + 4y + 5z = 7 replace x and y
-4(2-z)+4*6 + 5z = 7
-8 + 4z + 24 + 5z = 7
16 + 9z = 7
9z = 7 - 16
9z = -9
z = -9/9
z= -1
Finally
x= 2-z replace z
x = 2- (-1)
x = 3
the system has no solution.
Option C is correct.
Step-by-step explanation:
We need to solve the system of equations by substitution

Putting value of x from eq(2) into eq(1)

As as 0≠4is not true, we cannot find the value of y so the system has no solution.
Option C is correct.
Keywords: System of equations
Learn more about system of equations at:
#learnwithBrainly
9514 1404 393
Answer:
375 hamburgers
Step-by-step explanation:
Let h represent the number of hamburgers. Then h+63 is the number of cheeseburgers, and the combined total is ...
h +(h +63) = 813
2h = 813 -63 = 750
h = 750/2 = 375
375 hamburgers were sold on Saturday.
_____
<em>Additional comment</em>
In a "sum and difference" problem like this, the smaller number is half the difference between the sum and the difference. h = (813 -63)/2 = 375. This generic solution applies to all "sum and difference" problems.
(5 radical 2)^2 =
5^2 × (radical 2)^2 =
25 × 2 = 50
Answer:
60%
Step-by-step explanation:
If I get you right, you're asking for the percentage gain to the nearest percentage, right?
Now to do this, we need to get the amount of profit she made. That's quite easy, we only need to subtract the cost price from the selling price. And that equals $15 - $9.38 that equals $5.62.
Now, we divide this value by the cost price and multiply by 100% to get the percentage gain.
I.e 5.62/9.38 × 100%.
That gives 59.9% , which equals 60% when approximated to the nearest percentage.