Write as a mathematical expression and solve. The sum of a number and 2 times the number is 21. Find the number. i really need h
1 answer:
Answer:
3.69 (rounded)
Step-by-step explanation:
Substitute x for "a number".
New equation: x(x + 2) = 21
Distribute and combine to form a single equation: x^2 + 2x - 21 = 0
Use quadratic formula, factoring, or graphing to get all possible answers.
Quadratic formula: , where A = x^2 coefficient, B = x coefficient, and C = constant.
-5.69, 3.69
Eliminate an incorrect answer that does not line up with the above equation.
3.69
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Which polynomial is equal to (-3x^2 + 2x - 3) subtracted from (x^3 - x^2 + 3x)?
<h3><u><em>Answer:</em></u></h3>The polynomial equal to (-3x^2 + 2x - 3) subtracted from (x^3 - x^2 + 3x) is
Given that two polynomials are: and
We have to find the result when is subtracted from
In basic arithmetic operations,
when "a" is subtracted from "b" , the result is b - a
Similarly,
When is subtracted from
, the result is:
Let us solve the above expression
<em><u>There are two simple rules to remember: </u></em>
- When you multiply a negative number by a positive number then the product is always negative.
- When you multiply two negative numbers or two positive numbers then the product is always positive.
So the above expression becomes:
Removing the brackets we get,
Combining the like terms,
Thus the resulting polynomial is found
Answer:
The graph of the inverse function is the same that the graph of the original function
Step-by-step explanation:
step 1
Find the equation of the function in the graph
Let
f(x) ---> the function in the graph
we know that
Is a linear function
take the points (0,6) and (6,0)
<em>Find the slope of the linear function</em>
<em>Find the the equation of the linear function in slope intercept form</em>
we have
---> the y-intercept is given
substitute
step 2
Find the inverse of the function f(x)
Let
y=f(x)
<em>Exchange the variables (x for y and y for x)</em>
Isolate the variable y
Let
In this problem the graph of the inverse function is the same that the graph of the original function