I’ll mark as brainliest

f(x) = 2x + 5x - 1 = 139.

f = 139/20

x = 20

Hope this helps!! :)

Numbers inside {this} means you have to find the Least Common Factor of them.

So, the least common factor of them is 20 as:

2 = 2

-5 = -5

4 = 2².

The least common factor will be 2²*5 = 20.

Now, we plug in x as 20 to figure out f, which we will plug in again later to see the answer.

f*20 = 2x + 5x - 1

20f = 7x - 1

Remember, x = 20, so let's subsitute x as 20.

20f = 7(20) - 1

20f = 140 - 1 = 139

f = 139/20.

Let's plug f as 139/20 and x as 20 to see the final answer!!

139/20*20 = 2x + 5x - 1

139 = 7(20) - 1

139 = 139

We are correct!

-1/2 +2

step-by-step explanation: