Question #ad6a9

3 Answers
Jan 10, 2018

W(-8)=-27

Explanation:

"to evaluate "W(-8)" substitute x = - 8 into "W(x)

rArrW(color(red)(-8))=(4xxcolor(red)(-8))+5

color(white)(xxxxxxxx)=-32+5=-27

Jan 10, 2018

-27

Explanation:

Have a look at https://socratic.org/help/symbols Particularly note the hash at the beginning and end of the entered 'maths bit' This initiates and ends maths formatting. Example: hash 2x xx3 hash gives 2x xx3 Note the gap between x and xx. No gap gives 2xxx3
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color(green)(W(color(red)(x))=4color(red)(x)+5

The W is just a name that that is assigned to the structure of the expression 4("something")+5

So every time you see W (for this question) you know they are talking about the structure 4("something")+5

So color(green)(W(color(red)(-8))=[4xx(color(red)(-8))]+5

Set color(green)(y=W(color(red)(-8))

color(green)(y=[4xx(color(red)(-8))]+5)

y=-32+5=-27

Jan 10, 2018

-27

Explanation:

W(x) = 4x+5
when x=-8
W(x) = 4 . (-8) +5
-32+5 = -27