2-14:
A) 3x+5y=3(3)+5(2)
=9+10
=19
B) x²+y²=3²+2²
=9+4
=13
C) -5x+9=-5(3)+9
=-15+9
=-6
D) xy-1=(2×3)-1
=6-1
=5
E) 2x²-y=2(3)²-2
=18-2
=16
F) 2y-x+5+x²-3y=2(2)-3+5+3²-3(2)
=4-3+5+9-6
=9
2-15: area=y²+xy+xy
=(y²+2xy) un²
perimeter=y+y+y++y+x+y/2+y+x+y/2
=(6y+2x) un
