The formula to determine the distance from a point (xo,yo) to a line Ax+By+C=0 is:
`d=|Ax_o + By_o + C|/sqrt(A^2+B^2)`
To apply, set one side of the given equation equal to zero.
`y=-2x-3`
`2x+y+3=0`
Then, plug-in the coefficients of x and y, as well as the constant to the formula.
`d=|2x_o +1y_o +3|/sqrt(2^2+1^2)`
`d=|2x_o + y_o +3|/sqrt5`
And, plug-in the given point (4,-4).
`d=|2(4)+(-4)+3|/sqrt5`
`d=7/sqrt5`
`d=7/sqrt5*sqrt5/sqrt5`
`d=(7sqrt5)/5`
Therefore, the point (4,-4) is `(7sqrt5)/5` units away from the line y=-2x-3.
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