Respuesta :
Answer:
y= -4
Step-by-step explanation:
x+y=42. We know that x plus y equals 42.
x=2y . We also know that x equals twice y.
2y+y=42. Since we know that x=2y, we're going to replace x with 2y from the original equation, simplified would be 3y=42.
y=14. 3y=42 simplified is y=14, this is because we divided both sides by 3 (since 3 and 42 are both divisible by 3) (btw divisible by 3 simply means that it can be divided by 3)
x+14=42. Now that we know what y equals, let's replace y with 14 from the original equation.
x=28. Now that we know that x=28 and y=14, we know that y is always x/2.
When x=-8, we divide it by 2 and get, -4.
Not absolutely positive as this was all mental math, but hope this helps! :)
The value of the variable y at x = -8, will be negative 49.
What are ratio and proportion?
A ratio is a collection of ordered integers a and b represented as a/b, with b never equaling zero. A proportionate expression is one in which two items are equal.
The numbers x and y are inversely proportional. Then we have
y ∝ 1/x
y = k/x ...1
When the sum of x and y is 42. Then the equation will be
x + y = 42 ...2
x is twice y. Then the equation will be
x = 2y ...3
From equations 2 and 3, we have
2y + y = 42
3y = 42
y = 14
Then the value of x will be
x = 2(14)
x = 28
Then the value of k will be
14 = k / 28
k = 392
Then the equation will be
y = 392 / x
Then the value of the variable y at x = -8, will be
y = 392 / (-8)
y = -49
Thus, the value of the variable y at x = -8, will be negative 49.
More about the ratio and the proportion link is given below.
https://brainly.com/question/14335762
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