Question

if a/b=7/9 then what the value of 5a +3b /5a -3b​

Answer 1

Step-by-step explanation:

$\frac{a}{b} = \frac{7}{9}$

so, a= 7 and b=9

$\frac{5a + 3b}{5a - 3b}$

$= \frac{5 \times 7 + 3 \times 9}{5 \times 7 - 3 \times 9}$

$= \frac{35 + 27}{35 - 27}$

$= \frac{72}{8}$

$= 9$

The value of the expression is 9

Answer 2

a/b = 7/9

b=9a/7

b = 1.285a

Now, 5a +3b/5a -3b = 5a +3*1.285a /5a -3*1.285a

= 5a +3.855a /5a -3.855a

= 8.855a /1.145a

= 7.734

~ 31/4

Note: value of b should have been written as 9a/7 but points are taken due to inconvenience in typing.

Correct answer = 31/4