Mathematics
Grade10
Easy
Question
In the inverse variation , x = -8 when y = -
. What is the value of y when x = 4 ?
![1 over 8](data:image/png;base64,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)
- -2
![1 half](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAAjCAYAAACZ6FpfAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAABGJhU0UAAAAXQ/cXWQAAAJFJREFUeNpjYMAP1IC4FogvMFAIFgNxGhD/Z6ASGDVo1KBBYdB/LHgUDCbwn0w8CgYLsAbiNUD8CYh/QaujaHIMOgjEkUDMA+VrAfFRqBjFQB6IL1HLyz+oYYgl1HsUAQ4gPgmNBLKBIBBvAGI3SgxRghqiQokhGkA8G4i5KDFEHIhXATELpYG7BeoimhZyWAEAI3M1I31CbrEAAABidEVYdE1hdGhNTAA8bWF0aCB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMTk5OC9NYXRoL01hdGhNTCI+PG1mcmFjPjxtbj4xPC9tbj48bW4+MjwvbW4+PC9tZnJhYz48L21hdGg+ND6jrQAAAABJRU5ErkJggg==)
- -
![1 fourth](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAAjCAYAAACZ6FpfAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAABGJhU0UAAAAXQ/cXWQAAAGxJREFUeNpjYMAP1IC4FogvMFAIFgNxGhD/Z6ASGDVo1KBBYdB/LHgUDCbwn0w8CgYr8KFGDPEA8TVqGDQTiJMpNcgaiPdSWiaxAfElIJan1KAOIM6htJTUA+Kj1ChuTwKxCjUMommOH2J1GwCVNzk6FQ24cQAAAGJ0RVh0TWF0aE1MADxtYXRoIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8xOTk4L01hdGgvTWF0aE1MIj48bWZyYWM+PG1uPjE8L21uPjxtbj40PC9tbj48L21mcmFjPjwvbWF0aD7CA6ZrAAAAAElFTkSuQmCC)
Hint:
Mathematical relationship between two variables which can be expressed by an equation in which the product of two variables is equal to a constant.
The correct answer is: ![1 half](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAAjCAYAAACZ6FpfAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAABGJhU0UAAAAXQ/cXWQAAAJFJREFUeNpjYMAP1IC4FogvMFAIFgNxGhD/Z6ASGDVo1KBBYdB/LHgUDCbwn0w8CgYLsAbiNUD8CYh/QaujaHIMOgjEkUDMA+VrAfFRqBjFQB6IL1HLyz+oYYgl1HsUAQ4gPgmNBLKBIBBvAGI3SgxRghqiQokhGkA8G4i5KDFEHIhXATELpYG7BeoimhZyWAEAI3M1I31CbrEAAABidEVYdE1hdGhNTAA8bWF0aCB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMTk5OC9NYXRoL01hdGhNTCI+PG1mcmFjPjxtbj4xPC9tbj48bW4+MjwvbW4+PC9tZnJhYz48L21hdGg+ND6jrQAAAABJRU5ErkJggg==)
We have to find the value of y when x is 4.
We have, y = ![straight k over straight x](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAAjCAYAAACZ6FpfAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAABGJhU0UAAAAXQ/cXWQAAAMlJREFUeNpjYMAN/jNQCQxug8yBeBMQs1FikBIQ7wdiQUpcJArEJ4FYklKv7YV6i+IwMoWGDQ81Ahvkoi1AzEGNWLME4g3kGoaejqyBeB05hmFLkPZQw1gYRsHgAP/JxKNgFNAUgMqb40AsjSYOqgjOkFoe6QDxNjQxUHHrRo7LcoA4C8qOB+LFlHhzFbRUvAvEwpQYZAvEv4A4jRJDmID4MBBHQ8OHbNAIxIlQdiwQTyDHEFNo+CCDPqiBJKWj3ThaH9uglSUGAABvwzKZZYEtgQAAAIx0RVh0TWF0aE1MADxtYXRoIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8xOTk4L01hdGgvTWF0aE1MIj48bWZyYWM+PG1pIG1hdGh2YXJpYW50PSJub3JtYWwiPms8L21pPjxtaSBtYXRodmFyaWFudD0ibm9ybWFsIj54PC9taT48L21mcmFjPjwvbWF0aD5Y6RYsAAAAAElFTkSuQmCC)
=>-
= ![fraction numerator straight k over denominator left parenthesis negative 8 right parenthesis end fraction](data:image/png;base64,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)
=>k = 2.
So, y =
=
=
.
Hence, the correct option is B.
In inverse variation, we have x1y1 = x2y2.