100 POINTS

The numerator is 2 less than the denominator. If I add 3 both to the numerator and the denominator, the answer would be 5/6. what's the original fraction? ​

Respuesta :

Answer:

[tex]\dfrac{7}{9}[/tex]

Step-by-step explanation:

Let x be the denominator.

If the numerator is 2 less than the denominator, then the expression for the numerator is (x - 2):

[tex]\dfrac{x-2}{x}[/tex]

If 3 is added to both the numerator and the denominator, and the answer is 5/6, then:

[tex]\dfrac{x-2+3}{x+3}=\dfrac{5}{6}[/tex]

Now we can solve the equation for x.

Simplify the numerator in the fraction on the left of the equation:

[tex]\dfrac{x+1}{x+3}=\dfrac{5}{6}[/tex]

Cross mutliply:

[tex]6(x+1)=5(x+3)[/tex]

Expand the brackets:

[tex]6 \cdot x +6 \cdot 1 = 5 \cdot x + 5 \cdot 3[/tex]

[tex]6x+6=5x+15[/tex]

Subtract 5x from both sides of the equation:

[tex]6x+6-5x=5x+15-5x[/tex]

[tex]x+6=15[/tex]

Subtract 6 from both sides of the equation:

[tex]x+6-6=15-6[/tex]

[tex]x=9[/tex]

Therefore, the value of x is 9.

Now substitute the found value of x into the original rational expression:

[tex]\dfrac{x-2}{x}=\dfrac{9-2}{9}=\dfrac{7}{9}[/tex]

Therefore, the original fraction is:

[tex]\boxed{\dfrac{7}{9}}[/tex]