To solve the first equation, 7•x - 5 = 86, we first add 5 to both sides:

7•x - 5 + 5 = 86 + 5
7•x = 91

Next, divide both sides by 7 to solve for x:

x = 91/7
x = 13

Therefore, x = 13.

For the second equation, 250/(y+7) = 25, we first multiply both sides by (y+7) to get rid of the denominator:

250 = 25(y+7)

Next, distribute the 25 on the right side:

250 = 25y + 175

Subtract 175 from both sides:

250 - 175 = 25y
75 = 25y

Divide both sides by 25 to solve for y:

y = 75/25
y = 3

Therefore, y = 3.