<span>х+у и х-у
+ 2x
- -2y
* x</span>²-y²
: (x+y)/(x-y)
<span>b^2+24b+144= b^2+2*12*b+12^2=(b+12)^2</span>
!!!!!!!!!!!!!!!!!!!!!!!!!!!
1.t.......7č.
2.t.......xč.
dve.....3č.50min.= (3+5/6)č. = 23/6č.
1č. 1.t. 1/7
2.t. 1/x
dve....6/23
1/7+1/x=6/23 /.23.7.x
23x+161=42x
19x=161,x=161/19,x=(8+9/19)č.