<p><a href="http://i38.tinypic.com/29kxoie.jpg%5B/url%5D">http://i38.tinypic.com/29kxoie.jpg</a></p>
<p>(x-a)^5 = (x-a)k^4</p>
<p>In the equation above, x and k are positive numbers and 0 < a < x. Which of the following must be equal to x?</p>
<p>A. k
B. k-a
C. k+a
D. a ^4
E. k ^4 + a</p>
<p>#20</p>
<p>put the info into the figure and you’ll find that the 5-tile block in the figure has an area of (2+1)*(2+1)=9</p>
<p>area of rectangular section of the floor to be covered=24*15=360</p>
<p>number of 5-tiles-blocks needed to cover the section of the floor=360/9=40</p>
<p>number of tiles in 40 5-tiles-blocks= 40*5= 200</p>
<p>Answer is C. k+a</p>
<p>here are the steps:</p>
<p>1) (x-a)^5 = (x-a)k^4</p>
<p>2) [(x-a)^5/(x-a)] = k^4 divide both sides by (x-a)</p>
<p>3) You get (x-a)^4 = k^4 remember when you divide exponents of the same term like (x-a) you can subtract the exponents like this : (x^2)/x = x </p>
<p>4)Take the “fourth root” of both sides and get x-a = k </p>
<p>5) Simplify… x = k+a</p>
<p>Sometimes these exponent problems drop into place if you write things out like a beginner:</p>
<p>If (x-a)^5=(x-a)k^4</p>
<p>then (x-a)(x-a)(x-a)(x-a)(x-a) = (x-a)<em>k</em>k<em>k</em>k</p>
<p>The 5 terms on each side of the equal sign can only come out the same if x-a = k so x=k+a</p>
