[tex]a)\\\\ podstawa:\ a=8x+4\\wysokosc:\ h=\frac{1}{2}x\\\\pole\ trojkata\\\\P=\frac{1}{2}ah\\\\P= \frac{1}{2}(8x+4) * \frac{1}{2}x=\frac{1}{4 }x(8x+4)=2x^2+1[/tex]
[tex]b)\\\\ przekatna:\ e=6x^2 \\ przekatna:\ f=x+3\\\\pole\ rombu:\\\\P=\frac{1}{2}*6x^2(x+3)=3x^2(x+3)=3x^3+9x^2[/tex]
[tex]c)\\\\ podstawa:\ a=x^2+x+1\\podstawa:\ b=5x^2+2x+5 \\wysokosc\ trapezu :\ h=\frac{1}{3} x\\\\ pole\ trapezu:\\\\P=\frac{a+b}{2}*h\\\\P=\frac{ x^2+x+1+5x^2+2x+5}{2} *\frac{1}{3}x=\frac{ 6x^2+3x+6}{2} *\frac{1}{3}x =\\\\=\frac{\not{3}^1 *(2x^2+ x+2)}{2} *\frac{1}{\not{3}^1}x =\frac {2x^3+ x^2+2x }{2}=x^3+\frac{1}{2}x^2+x[/tex]
