Since both angle are congruent (equal/same), which means that both side is equal to 40 degrees, we will put the equation like this:
5x - 5 = 40
Now we’ll solve for x:
5x - 5 = 40
+ 5 + 5 (Add 5 to both sides)
5x = 45
—- —— (Five both side by 5)
5 5
x = 9
Now we left with x, so x is equal to 9.