contestada

Solve for the given length: The length of a rectangle is 3 m longer than its width. The area of the rectangle is 154 m2. What is the width of the rectangle?

Respuesta :

calculista
Let 
X-----------> is the length of rectangle
y----------> is the width of rectangle

 we know that
x=y+3-----------------> equation 1
A=x*y--------> x*y=154----------> equation 2
substituting 1 in 2

(y+3)*y=154-----------> y²+3y-154=0
y²+3y-154=0

using a graph tool----------> to calculate the quadratic equation
see the attached figure

the solution is
y=11 m
x=y+3--------> x=11+3---------> x=14 m

the answer is
the width is 11 m
Ver imagen calculista
To get this answer you would use the formula A = lw to find the missing dimension.

You will substitite in what you know the area is and an expression for the length.

154 = w (3 + w)
154 = 3w + w^2

Create an equivalent equation equal to 0.
w ^2 + 3w -154 =0
(w - 11 ) (w + 14) = 0
w would be either 11 or -14 for this to be true.

Only 11 is a possible dimension, so the width is 11 meters.

Otras preguntas