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What is the area of the two rectangles shown below?

What is the area of the two rectangles shown below?-example-1
User Myroslav
by
3.2k points

2 Answers

10 votes

Answer:

-- I don't know if you'll still need mine, but here's what I got --

1st (shaded) box = Area is 441

2nd (shaded) box = Area is 1,764

Explanation:

First of all, It stated, "To determine the area of the (shaded) portion" but it didn't mention the white box so I ignored it and pay attention only to the "shaded box" as mentioned in the assignment

1st (shaded) box

1. write it out like so,
4x + 7 = 3x

2. next to get "x" alone subtract 7 to the other side once done you would have this,
4x=3x-7

3. then subtract 3x to both sides...
3x-3x=cancelsout >>
4x-3x=1x=x >> you're now left with,
x=-7

To find the area we need one more step...


4x+7=4(-7)+7=-28+7=-21 and
3x=3(-7)=-21 then multiply to get the area, negative crosses each other out once multiplying so -21 times -21 gives you 441

-------

2nd (shaded) box repeat from above

1.
8n+14=6n

2.
8n=6n-14

3.
2n=-14, here is different as there is still one more step, we need to divide to get "n" alone.

4.
(2n=-14)/(2) = n=-7

Now plugin to get the area,
6n=6(-7)=-42\\8n+14=8(-7)+14=-56+14=-42\\ once multiplied you get 1,764

Once again I could be wrong but this is what I got after reading the little description from your attached assignment.

User Alu
by
3.6k points
9 votes

Answers are in bold.

For the first one:

The total area of both shaded and unshaded portions is equal to
3x(4x+7), which simplifies to
12x^2}+21x. The area of the middle white portion is
(5x)(2x), which simplifies to
10x^2. To find the area of the shaded portion, we do
12x^2}+21x - 10x^2. Combining like terms, we get
2x^2+21x as our expression for the area of the shaded portion of the first rectangle.

For the second one:

The total area of both shaded and unshaded portions is equal to
6n(8n+14), which simplifies to
48n^2}+84n. The area of the middle white portion is
10n(4n+1), which simplifies to
40n^2+10n. To find the area of the shaded portion, we do
48n^2+84n-40n^2+10n. Combining like terms, we get
4n^2+94n as our expression for the area of the shaded portion of the second rectangle.

User Lpil
by
3.3k points