Respuesta :
Greetings from Brasil...
Here we will use media products
A/B = C/D ⇔ A · D = B · C
5/7 = X/9 ⇔ 7 · X = 5 · 9
7X = 45
X = 45/7

Answer:
7/45
Step-by-step explanation:
Because the x because its the constant which stay the same and it signify the numerator and once you times the x to 7 its is equals 7. The denominator is 9 which will be 5 times equal 45. That why it equals 7/45.