Sagot :
We have ( 4x + 3y ) : ( 3x + 4y ) = 24 : 25
[tex]\\ \sf\longmapsto \: \frac{4x + 3y}{3x + 4y} = \frac{24}{25} [/tex]
[tex]\\ \sf\longmapsto \: 25(4x + 3y) = 24(3x + 4y)[/tex]
[tex]\\ \sf\longmapsto \: 100x + 75y = 72x + 96y[/tex]
[tex]\\ \sf\longmapsto \: 100x - 72x = 96y - 75y[/tex]
[tex]\\ \sf\longmapsto \: 28x = 21y[/tex]
[tex]\\ \sf\longmapsto \: \frac{x}{y} = \frac{21}{28} = \frac{3}{4} [/tex]
Hence ,
- x : y = 3 : 4
[tex]\\ \sf\longmapsto \dfrac{4x+3y}{3x+4y}=\dfrac{24}{25}[/tex]
- Use cross multiplication
[tex]\\ \sf\longmapsto 24(3x+4y)=25(4x+3y)[/tex]
[tex]\\ \sf\longmapsto 72x+96y=100x+75y[/tex]
[tex]\\ \sf\longmapsto 96y-75y=100x-72x[/tex]
[tex]\\ \sf\longmapsto 21y=28x[/tex]
[tex]\\ \sf\longmapsto \dfrac{x}{y}=\dfrac{21}{28}[/tex]
- Cut 7
[tex]\\ \sf\longmapsto \dfrac{x}{y}=\dfrac{3}{4}[/tex]
[tex]\\ \sf\longmapsto x:y=3:4[/tex]