The scenario will will be represented by: 
The number will be -13
Step-by-step explanation:
We have to convert the given situation into the mathematical form
Let x be the number
Then
"a number plus itself"
x+x
"plus twice itself"
x+x+2x
"plus 4 times itself"
x+x+2x+4x
"is equal to -104"

This can also be written as:

Keywords: Linear Equation
Learn more about linear equation at:
#LearnwithBrainly
Answer:
x=-7
Step-by-step explanation:
first, subtract 4x from both sides. then you'll get:
-9=3x+12
next subtract 12 from both sides. Then you'll get:
-21=3x
then you divide each side by 3. You get:
x=-7
Answer:
The answer is 3 inch
Step-by-step explanation:
To start off, the equation you want to use the formula V=whl
Next, you simply plug in the values you already know, so you have 450=w*20*7.5
After you do that you multiply 20 times 7.5 to get which is 150, which leaves you with 450= w *150 to solve for w, you need to isolate it. To do that you divide 450 by 150. You are left with the answer of 3.
Answer:
18 inches and 9 inches
Step-by-step explanation:
Given, The base of a triangle is twice of the height.
Area = 81 sq inches
Let, Base (b) = 2x
Height (h) = x
Area of the triangle = \frac{1}{2}bh
\frac{1}{2}bh = 81
or, x^{2} = 8
Base = 2×9 inches = 18 inches
Height = 9 inches