Explanation:
The starting system is:
{
0.4
x
−
0.1
y
=
2
0.2
x
+
0.5
y
=
1
If we multiply the second equation by
−
2
the coefficients of
x
will be opposite numbers:
{
0.4
x
−
0.1
y
=
2
−
0.4
x
−
y
=
−
2
Now we can add both sides of the equations to get an euation of 1 variable:
−
1.1
y
=
0
y
=
0
Now we have to substitute the calculated value of
y
to calculate
x
:
0.4
x
=
2
x
=
2
0.4
=
20
4
=
5
Answer:
The solution of this systemm is:
{
x= 5
Y=0
I hope that helps let me know if you have questions.
Answer:
Which answer do you need
Step-by-step explanation:
Answer: 29 cows
Step-by-step explanation:
First we need to know how many pieces of meat will be needed. But before that, we need to know how many hours are in these 30 days. 24 hours per day so, 30*24=720 hours. 720 hours and 4 pieces of meat per 10 of those hours. We can do 720/10=72, then, 72*4=288. That means we need 288 pieces of meat, if each cow gives you ten, then we can round 288 to the nearest ten which is 290, then, 290/10 is 29. This means that Dumbledore needs 29 whole cows.
<em>(Yer a wizard Harry)</em>