Which equation could you use to solve for x in the proportion StartFraction 4 over 5 EndFraction = StartFraction 9 over x EndFraction? 4 x = 14 4 x = 45 5 x = 13 5 x = 36

(b) 4 x = 4 5 is the needed expression to solve for the value of x.

Step-by-step explanation:

Here, the given proportion is simplified as:

Now, to simplify any proportion of the form  the simplest way is CROSS MULTIPLICATION.

So, cross multiplying  

Similarly cross multiplying , we get:

4 (x)  = (9) (5)

or, 4 x  = 45

Hence, 4 x = 45 is the needed expression to solve for the value of x.

77

step-by-step explanation: