Hello, princess_anna57!
Sketch the graph: .f(x) .= .(4x  16)^{½}
We have: . y .= .(4x  16)^{½} . → . y(4x  16)^{½} .= .1
Square both sides: . y²(4x  16) .= .1 . → . 4y²(x  4) .= .1
And we have: . x  4 .= .1/(4y²) . → . x .= .(1/4y²) + 4
The graph of: .x .= .1/(4y²) .looks like this: Code:
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The graph of: .x .= .1/(4y²) + 4 .is translated 4 units to the right.
In the original function, we see that y is always positive.
. . Hence, we want only the upper "half" of the graph. Code:
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 4