<span>1/2x+3y/4=5 => (1/2)x + (3/4)y = 5
1/5x+3y/2=2 => (1/5)x + (3/2)y = 2
Eliminate the fractional coefficients: Mult. the first equation by 4 and mult. the second equation by 10:
2x + 15y = 20
</span><span>Multiply the 1st equation by -1:
-</span>2x - 3y = -20
2x + 15y = 20
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12y = 0, so y = 0. Then the first equation becomes 2x + 3(0) = 20, or
x=10.
Solution is (10,0).
Step-by-step explanation:
n2+5=21
n2 =21-5
n2 = 16
n =16/2=8
Answer:
The solution is x = -2, y = -3
Step-by-step explanation:
Let's start with the equation 3x + y = -9
Substitute the y for 5x+7 seen in the second equation
Now you have 3x + (5x+7) = -9
Lets solve:
Let's add the x's
Now we have 8x + 7 = -9
Substracy seven from each side
Now we have 8x = -16
Now let's divide 8 on each side
Now we have x = -2
Now lets plug in -2 to the second equation
The second equation is y = 5x+7
When we plug in -2 we get y=5(-2)+7
We multiply
We now have y = -10+7
Add
y = -3
The solution is x = -2, y = -3
To get the answer, all you have to do is 715 ÷ 55 which equals 13 (hours)