The length of a rectangle is (2x –1) units, and the width is (x − 2) units. the area of the rectangle is 20 square units. what is the length of the rectangle?

a. 0.5 units

b. 3 units

c. 4.5 units

d. 8 units

Length of the given rectangle is 8 units.

Option - D

Solution:

Given that  

Length of a rectangle =

Width of a rectangle =

Area of rectangle = 20 square units  

Need to calculate length of rectangle.

Substituting given value of Area of rectangle and expressions for length and width of rectangle in formula, we get

On solving above equation for x we get

On splitting the middle term in such a way that product of split terms comes as and summation comes as -5x, we get

As length cannot be negative hence we can ignore negative value.

So length is 8 units.

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form

2x+60=

step-by-step explanation: