Respuesta :

Answer:

Option 4 is not true

Step-by-step explanation:

[tex]\frac{a}{b}=\frac{c}{d}\\\\[/tex]

1)Cross multiply,

ad = bc

So, true

2) a/ c = b/d also true

3) a+b/b = c+d/d  also true

For example:

[tex]\frac{1}{4}=\frac{2}{8}\\\\\frac{1+4}{4}=\frac{2+8}{8}\\\\\frac{5}{4}=\frac{10}{8}\\\\[/tex]

When simplifying 10/8, it is 5/4.

5) b/a = d/c is also true