The area of a rectangle is 45 ft2. if the length of the long side of the rectangle is 80% greater than the short side of the rectangle, what is the length of the longer side?

To solve this problem we propose the following equation:

1)  This is the equation of the area of a rectangle.

Where a and b are the sides of the rectangle

If b is the longest side, then

b is 80% longer than h.

2)

Now we have 2 equations and two unknowns.

Therefore we solve the following equations

b = 9 feet

The length of the longest side is 9 feet.

d, x=8

step-by-step explanation:

simplifying

4x + -5 = 2x + 11

reorder the terms:

-5 + 4x = 2x + 11

reorder the terms:

-5 + 4x = 11 + 2x

solving

-5 + 4x = 11 + 2x

solving for variable 'x'.

move all terms containing x to the left, all other terms to the right.

add '-2x' to each side of the equation.

-5 + 4x + -2x = 11 + 2x + -2x

combine like terms: 4x + -2x = 2x

-5 + 2x = 11 + 2x + -2x

combine like terms: 2x + -2x = 0

-5 + 2x = 11 + 0

-5 + 2x = 11

add '5' to each side of the equation.

-5 + 5 + 2x = 11 + 5

combine like terms: -5 + 5 = 0

0 + 2x = 11 + 5

2x = 11 + 5

combine like terms: 11 + 5 = 16

2x = 16

divide each side by '2'.