9x+3y=-68
-2x+y=18
We are asked to solve with substitution so we first write y=18+2x.
Let us substitute this into the first equation.
9x+3(18+2x)=-68
9x+54+6x=-68
15x=-68-54=-122
so x=-122/15
and y =18+2(-122/15)==18+-244/15=270/15-244/15=26/15
So the solution is (-122/15,26/15) which is an ordered pair.
Why are factors in formulas squared eg gravity energy etc?
The simplest answer would be that it is simple the way it is. A linear change in distance and gravity just doesn't match up with reality. So a better answer is that this is way it must be. Nothing else really describes what is happening.
What is the factor of x to the power of 3-3x to the power of 2-9x plus 27?
x3 - 3x2 - 9x + 27
= x2(x - 3) - 9(x - 3)
= (x - 3)(x2 - 9)
= (x - 3)(x - 3)(x + 3)
What is the legality of D and X?
Several states have taken legal action to limit or ban D and X.March 2003,the United States Senate passed a bill banning partial birth abortions.but a federal judge declared the law unconstitutional,so that the government had not been able to enforce it.
How do you plug in cords in y equals mx plus b?
Y=m*x+b
Y = Y coordinate
M = slope
X = X coordinate
B = Y intercept
To get a coordinate just put a number into X and see what Y comes out as.
example:
Y = 2x - 1
coordinates:
(X,Y)
(-3,-7)
(-2,-5)
(-1,-3)
(0,-1)
(1,1)
(2,3)
(3,5)
What is the factorization of 2x2-6X plus 24?
There are no solutions to this quadratic equation because the discriminant is less than zero.
If x equals 1 3 when y equals 162 find x when y equals 3?
You need to know what is the relationship between x and y. Are they proportional? Inversely proportional? Several other options also exist.
What is the integral of one over the square root of forty-nine minus x squared?
Very sorry, I showed you how to take the derivative of the stated problem. I leave that below, however to take the integral you really just need your table of integrals.
The reference integral from my table (in my old calculus book) is:
integral of 1 / [ a2 - x^2]1/2 = sin-1|x / a| + c
a2 = 49 => a=7
x2 = x^2 => x = x
And your answer is:
sin
-1(x / 7) + c
If you are not allowed to use the table of integrals, the other alternative is trigonometric substitution.
Assume our integral is:
The integral of dx / sqrt ( a2 - x2)
Let x = a sin (θ)
dx = a cos (θ) d
θ
<-- this is just the derivative of x
θ = sin-1 (x/a) <-- solve the first equation for theta
So the integral transforms into:
the integral of ( a cos (θ)
d
θ
) / sqrt ( a2 -
a2sin2(θ) )
factor out an a2 in the root:
( a cos (θ)
d
θ
) / sqrt (
a
2 (1
-
sin2(θ) ) )
use the trig identity: sin2
(θ) + cos2
(θ) = 1
which can be rewritten:
1
-
sin2(θ) =
cos2
(θ)
and therefore:
( a cos (θ)
d
θ
) / sqrt (
a
2(
cos2
(θ)
) )
which simplifies to:
( a cos (θ)
d
θ
) /
( a cos (θ) )
which leaves us with the integral of
d
d
θ
it's now easy to solve and we get:
θ + C
plugin theta (from above):
sin
-1(x/a) + C
Plus in your a and x from the original equation, and you are good to go.
-----
Bonus: Here is how you find the derivative of this, since I already solved this on accident:
First, rewrite the expression to kill the fraction:1/(49-x2)1/2 =(49-x2)-1/2
Now, we can use u-substitution.
Let u = 49-x2
u` = -2x
Take thederivativeof u-1/2
(u-1/2)`= [ -u-3/2 ]/ 2
Now multiply by u`.
( [ -u-3/2]/ 2 ) ( -2x ) = (the 2's and negatives cancel)
x [ u-3/2] =
x / u3/2
Now plug u back in (remember: u = 49-x2)
x / u3/2 = x / (49-x2)3/2
The answer is:
x / (49-x2)3/2
Can you solve the equation 4x squared plus 7 equals 5?
Yes, but the solution is imaginary if you have learned that
4x^2 + 7 = 5
4x^2 = -2
x^2 = -1/2
x = +/-0.707i where i = square root of -1
How do you factor 4x2 plus 2x-6 equals 0?
If 4*2+2x-6=0 is what you meant, then I am going to say 2(2*1+1x-3) is your answer
Edit: if solving for x then -1 is your answer, sorry I'm used to solving for multiple possibilities for x so "factor" threw me off.
I don't see any description.
However, the exponential function is defined for any value of the argument; on the other hand, since you have 1/x, zero is excluded. The function is defined for any value other than zero.
How do you solve 8x plus 8 equals 32x?
Equation: 8x + 8 = 32x. x = 1/3
Check answer in original equation: 8/3 + 8 = 32/3. Both sides equal 10 2/3, so our answer is correct.