X squared plus 7x plus 6 equals 0?
1
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1 is not correct.
The correct solution is x = -1 or -6.
You can easily find it this way:
Factorising, we obtain
x2 + 7x + 6 = (x + 1)(x + 6) = 0.
The above is true if, and only if, either,
x + 1 = 0, or, else,
x + 6 = 0; that is, if
x = -1 or -6, which is the answer we sought.
The rule is that two numbers multiply to give a product of zero, if, and only if, one of the two numbers is zero.
To check our answer, let's try substitution into the original equation:
Does (-1)2 + 7(-1) + 6 = 0?
We see that 1 - 7 + 6 = 0.
Does (-6)2 + 7(-6) + 6 = 0?
We see that 36 - 42 + 6 = 0.
The answer is yes, both times, thus assuring us that we have found the correct answer.
What is the discriminant of 3 x squared -2x plus 3?
The discriminant is.....
b^2 - 4ac
(-2)^2 - 4(3)(3)
4 - 36 = - 32
Less than 1 so no real roots.
How many interaction effects are possible for a 2 x 3 x 2 Analysis of Variance?
2 x 3 x 2 = 12 interactions
Do system of equations x plus 7y equals 2 and x equals 9-7y?
There is no solution. Your system looks like this:
x + 7y = 2
x = 9 - 7y
The first can be rewritten as x = 2 - 7y,
and then join the two as 9 - 7y = 2 - 7y
Adding 7y to both yields 9 = 2 which is false, so there's no solution.
You can convert these to slope/intercept form as:
y = -x/7 + 2/7
y = -x/7 + 9/7
These are parallel lines, and will never intersect, so there is no solution that satisfies both equations.
What is the resulting expression of f 2y if f x 2x 3x?
It is not possible to find the expression of 2y if f(x) = 2x - 3x.
If: x-2y+12 = 0 then x = 2y-12
If: x = 2y-12 then x^2 = (2y-12)^2 which is 4y^2-48y+144
If: x^2 +y^2 -x -31 = 0
Then: 4y^2 -48y +144+y^2 -(2y-12) -31 = 0
Removing brackets and collecting like terms: 5y^2 -50y +125 = 0
Divide all terms by 5 and factorize: (y-5)(y-5) = 0 => y = 5
Therefore by substitution solutions are: x = -2 and y = 5
How do you solve 3x plus 5 plus 2x plus 1 equals?
That's not an equation, it doesn't ask a question, and it's not looking for a solution.
Your teacher may have given it to you, and asked you to simplify it. Here's
how to 'solve' that assignment:
3x + 5 + 2x + 1
Add up all the 'x' terms: 3x + 2x = 5x
Add up all the number terms: 5 + 1 = 6
The original expression is equal to [ 5x + 6 ].
What value of x makes the expression x 2 and 2x equal?
Any value of x! Multiplication is commutative, that is, the order of multiplication doesn't matter, so 2x3=3x2, 23x45=45x23, and so on. Hence, 2 times x and x times 2 are the same. Therefore, it doesn't matter what x is!
But here is the simplest answer:
sin x * cos x = 1/2 sin 2x
You have enough fingers and toes to figure this one out (unless you are a redneck which might explain the question in the first place). The answer should also be memorized: 15. Please don't make a mockery of the calculus section.
Both the ellipse and the hyperbola has an x squared and a y squared term. In the ellipse, they are both positive. In the hyperbola, one of them is negative.
Example:
3x^2 /36 + 5y^2 / 64 = 1 (ellipse)
3x^2 / 36 - 5y^2 / 64 = 1 (hyperbola)
How do you solve 2x-y equals 4 and 2y equals 4x-6 using the substitution method?
2x-y = 4 and 2y = 4x-6
pick either equation and solve for one of the variables
the first equation: y = -4 + 2x
plug in the value of variable you solved for into the other equation
2(-4 + 2x) = 4x -6
then solve
-8 + 2x = 4x-6
-2 = 2x
x= -1
then plug in the value you have found into either original equation to find the value of the other variable
2(-1) - y = 4
-2 - y = 4
-y = 6
y = -6
The goal is to solve for a value of x such that the equation is true. The equation is:
8x + 5 = 7x + 8
First, subtract 5 from both sides, so that there is only a constant on the right side.
8x = 7x + 3
Next, subtract 7x from both sides, so that the variable, x, is only on the left side.
x = 3
The result is x = 3.
This is a quadratic equation requiring the values of x to be found.
Rearrange the equation in the form of:
-3x2-4x+6 = 0
Use the quadratic equation formula to factorise the equation:
(-3x+2.69041576)(x+2.23013857)
Therefore the values of x are 0.8968052533 or - 2.230138587
An even more accurate answer can be found by using surds instead of decimals.
24 = 3x + 9 -9 -9 Subtract 9 from each side
15 = 3x
/3 /3 Divide 3 from each side
5 = x You are left with five equals X