<span>Simplifying
4x + 20 = 6x + -10
Reorder the terms:
20 + 4x = 6x + -10
Reorder the terms:
20 + 4x = -10 + 6x
Solving
20 + 4x = -10 + 6x
Move all terms containing x to the left, all other terms to the right.
Add '-6x' to each side of the equation.
20 + 4x + -6x = -10 + 6x + -6x
Combine like terms: 4x + -6x = -2x
20 + -2x = -10 + 6x + -6x
Combine like terms: 6x + -6x = 0
20 + -2x = -10 + 0
20 + -2x = -10
Add '-20' to each side of the equation.
20 + -20 + -2x = -10 + -20
Combine like terms: 20 + -20 = 0
0 + -2x = -10 + -20
-2x = -10 + -20
Combine like terms: -10 + -20 = -30
-2x = -30
Divide each side by '-2'.
x = 15
Simplifying
x = 15</span>
Answer:
-1/5x -4/5 = y
Step-by-step explanation:
f(x) = -5x -4
y = -5x-4
Switch x and y
x = -5y -4
Solve for y
Add 4
x+4 = -5y
Divide by -5
-1/5x - 4/5 = -5y/-5
-1/5x -4/5 = y
We know that the perimeter is the all the sides added up together. Generally, you have

, where l is length and w is width.
For a square, all sides are of the same length, so you can write

, where x is any side.
If the smallest perimeter is 14, then

, so x is 3.5. If the largest perimeter is 72, then

, so x is 18.
Therefore, you have 3.5 ≤ x ≤ 18.