SOLUTION: A flat panel monitor are such that its length is 3 in. more than its width. If length were doubled and if the width were decreased by 1 in., the area would be increased by 150 in.2

Question 167152: A flat panel monitor are such that its length is 3 in. more than its width. If length were doubled and if the width were decreased by 1 in., the area would be increased by 150 in.2(squared). What are the length and width of flat panel monitor?
Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
A flat panel monitor are such that its length is 3 in. more than its width. If length were doubled and if the width were decreased by 1 in., the area would be increased by 150 in.2(squared). What are the length and width of flat panel monitor?
.
Let w = width of monitor
then
w+3 = length of monitor
.
double length = 2(w+3)
width decreased by 1 = w-1
.
2(w+3)(w-1) =150
2(w^2-w+3w-3) =150
2(w^2+2w-3) =150
w^2+2w-3 =75
w^2+2w-78 = 0
.
Using the quadratic equation to solve, we find the roots as:
w = {7.888, -9.888}
.
We can toss out the negative solution since it doesn't make sense.
w = 7.888 inches (width)
.
length:
w+3 = 7.888+3 = 10.888 inches (length)
.
Details of quadratic:

Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=316 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 7.88819441731559, -9.88819441731559. Here's your graph:

RELATED QUESTIONS
flat-panel monitor are such that its length is 3 in. more than its width. If the length... (answered by solver91311)

Please help me solve this word problem: The dimensions of a rectangular monitor screen (answered by rothauserc)

The dimensions of a rectangular monitor screen are such that its length is 5 in. more... (answered by josgarithmetic)

The dimensions of a rectangle are such that its length is 7 in more than its width. If... (answered by checkley77)

The dimensions of a rectangle are such that its lenghth is 3 in. more than its width. If (answered by solver91311)

The dimensions of a rectangle are such that it's length is 3 in. more than its width. If... (answered by ankor@dixie-net.com)

The dimensions of a rectangle are such that it's length is 7in more than its width. If... (answered by josgarithmetic)

The dimensions of a rectangle are such that its length is 9 in. more than its width.... (answered by lwsshak3)

The dimensions of a rectangle are such that its length is 5 in. more than its width. If... (answered by josgarithmetic)