Răspuns:
b)6
c)60
d)4
Explicație pas cu pas:
b)
[tex]\frac{6}{x} = \frac{y}{3}[/tex] => xy= 6*3=18
=> 96-5xy= 96 - 5*18 = 96 -90 = 6
c)
[tex]\frac{x}{13} =\frac{4}{y} [/tex] => xy= 13*4 = 52
=> 112- xy= 112- 52= 60
d)
[tex]\frac{x}{1,2} =\frac{0,5}{y}[/tex]
1,2= [tex]\frac{12}{10} [/tex] , simplificam prin 2 => 1,2 = [tex]\frac{6}{5} [/tex]
=> [tex]\frac{x}{1,2} [/tex] = [tex]\frac{x}{\frac{6}{5} } [/tex] = x * [tex]\frac{5}{6} [/tex] = [tex]\frac{5x}{6} [/tex] (1)
0,5= [tex]\frac{5}{10} [/tex], simplificam prin 5 => 0,5= [tex]\frac{1}{2} [/tex]
=> [tex]\frac{0,5}{y} = \frac{\frac{1}{2} }{y} [/tex] = [tex]\frac{1}{2} * \frac{1}{y} = \frac{1}{2y} [/tex] (2)
din (1), (2) => [tex]\frac{5x}{6} = \frac{1}{2y} [/tex] => 5x*2y = 1*6
10xy = 6
=> 10xy- 2= 6-2=4
