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(w-13)(w-13)=16
 Mar 19, 2014
 #1
avatar+124696 
+3
Note that (w-13) (w-13) = (w-13)^2

So we have (w-13)^2 = 16

Taking the square root of both sides, we have

(w-13) = 4

Add 13 to both sides .......so, w = 17
 Mar 19, 2014
 #2
avatar+64 
0
Remeber that: (a-b) 2 = a 2-2ab+b 2
So you have:
(w-13)(w-13)=16 =>
(w-13) 2=16 =>
w 2-2w*13+13 2=16 =>
w 2-26w+153=0 =>

Check, Quadratic equation: http://en.wikipedia.org/wiki/Quadratic_equation

w=(26+sqrt(26^2-4*153))/2

OR

w=(26-sqrt(26^2-4*153))/2

So there are 2 solutions!
w=9 OR w=17

Dms
 Mar 19, 2014
 #3
avatar+142 
0
femmy:

(w-13)(w-13)=16



FIRST:
Equal your equation to ZERO and do the equation of the (), w 2 - 26w + 169 = 16 /////// w 2 - 26w + 153 = 0

SECOND:
Use the formula

(-b +/- sqrt(b 2 - 4ac))/2a

You'll have w 1 and w 2

solve((w-13)(w-13)=16, w)
 Mar 19, 2014
 #4
avatar+118203 
0
CPhill:

Note that (w-13) (w-13) = (w-13)^2

So we have (w-13)^2 = 16

Taking the square root of both sides, we have

(w-13) = 4

Add 13 to both sides .......so, w = 17



I would have used CPhill's method
He just made a careless error

w-13=4 OR w-13=-4
 Mar 19, 2014

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