<span> x^2 +(x-4)^2 =20^2</span>
<span> x^2 +(x-4)^2 =400</span>
x^2 +(x-4)^2 -400=0
factor:
2x^2-8x-384=0
Factor the 2 out of 2X^2
2(x-16) (x+12) =0
<span> Divide both sides by 2</span>
(x-16) (x+12) =0
X=16 , x=-12
<span> Number cannot be negative so x=16</span>
Im thinking 10 because 10+40=50 and 10x7=70
Let's say that the shorter piece is x and the longer piece is 5x (because it's 5 times as long). x+5x=72 and 6x=72. Dividing both sides by 6, we get that x=12, and 72-12=the length of the other piece (since there are only 2 pieces)=60
To find the answer, you divide 5.50 by 5 to get the price of one slice of pizza. We get that one slice is $1.10. 2 slices would be $2.20. 10 slices would be $11. Half a slice would be $0.55. Hope this helps!