Answer:
Step-by-step explanation:
4x − y = −11
2x + 3y = 5
lets multiply the second equation by -2 and add it to the first:
4x − y = −11
-4x - 6y = -10
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0 - 7y = -21
y = -21/-7
y = 3
now we substitute this result in the first equation to find x:
4x − y = −11
4x - 3 = -11
4x = -8
x = -8/4
x = 2
so the solution is y = 3 and x =2
4x − 9y = −21
−10y = −30
we solve for y
−10y = −30
y = -30/-10
y = 3
and substitute in the first equation:
4x − 9y = −21
4x − 9(3) = −21
4x - 27 = -21
4x = 6
x = 6/4 = 3/2
so the solution is x = 3/2 and y = 3
4x + 3y = 5
2y = −6
we solve for y:
2y = −6
y = -6/2
y = -3
we do substitute in the first equation:
4x + 3y = 5
4x + 3(-3) = 5
4x - 9 = 5
4x = 14
x = 14/4
x = 7/2
so the solution is x = 7/2 and y = -3
7x − 3y = −11
9x = −6
we solve for x:
9x = −6
x = -6/9
x = -2/3
then we substitute in the first equation the result found:
7x − 3y = −11
7(-2/3) − 3y = −11
-14/3 - 3y = -11
we multiply by 3 to eliminate fractions:
-14 - 9y = -33
9y = 19
y = 19/9
so the solution is x = -2/3 and y = 19/9
12x − 3y = −33
14x = −28
we solve for x:
14x = −28
x = -28/14
x = -2
then we substitute in the first equation:
12x − 3y = −33
12(-2) − 3y = −33
-24 - 3y = -33
3y = 9
y = 3
then the solution is x = -2 and y = 3
Answer:
If all other factors are controlled, and the only variable being changed is the new medication, then Byron can conclude that the new medication is effective at reducing coughing. This can be further tested by repeated experiments by peers.
Step-by-step explanation:
So we need to cover 5.5% into a decimal.
0.055 = 5.5%
The house value is 120,000.
So
(1.055x) * (120,000)=
So
f(x)=1.055x * 120,000
Answer:
6 hours
Step-by-step explanation:
Given that:
Time taken by Sam = 3 hours
Sam's rate = 1/3
Time taken : Sam + Laura = 2 hours
Sam's rate + Laura's rate = 1/2
Let time taken by Laura = x
1/3 + 1/x = 1/2
1/x = 1/2 - 1/3
1/x = (3 - 2) / 6
1/x = 1 /6
x = 6
Hencw, it will take 6 hours for Laura alone to rake leaves
