[tex]( (\frac{1}{2}+ \frac{85}{10} ) . \frac{1}{18} ) ^{x} = \frac{1}{32}[/tex] ⇔ [tex]( \frac{5+85}{10} .\frac{1}{18} ) ^{x} = (\frac{1}{2} ) ^{5}[/tex] ⇔ [tex](\frac{90}{10} . \frac{1}{18} )^{x} = ( \frac{1}{2})^{5}[/tex] ⇔ [tex](\frac{1}{2} )^{x} = ( \frac{1}{2})^{5}[/tex] ⇒ x=5
m.a.ponderată = [tex]\frac{6 * 5 + 4 * 3}{5+3} = \frac{30+12}{8} =\frac{42}{8} = 21/4[/tex] (nu sunt sigură că este corect)
P = 2l +2L
L=3l ⇔ P = 2l +2*3l= 2l + 6l ⇒ P= 8l ⇒ l=32:8 ⇒ l= 4cm ⇒ L= 12cm
P triunghiului= a+b+c = 6 + 8+10= 24 cm
A triunghiului oarecare = [tex]\sqrt{p(p-a)(p-b)(p-c)} = \sqrt{12(12-6)(12-8)(12-10)} =[/tex][tex]\sqrt{12*6*4*2} = \sqrt{576} = 24 cm^{2}[/tex]
[tex]p = \frac{a+b+c}{2} = \frac{24}{2} = 12 cm[/tex]
R= ? ⇒[tex]A triunghiului = \frac{a*b*c}{4R}[/tex] ⇒[tex]R = \frac{a*b*b*c}{4A} = \frac{6*8*10}{4*24} = 5 cm[/tex]
