Answer:
x = 1, x = -1
Step-by-step explanation:
Given 
Use substitution
Square previous equality:
Substitute it into the equation:
Solve this quadratic equation:
Note that
then
so
Solve this equation using substitution
Thus,
![u+\dfrac{1}{u}=\dfrac{5}{2}\\ \\2u^2+2=5u\ \ [\text{Multiplied by 2u}]\\ \\2u^2-5u+2=0\\ \\D=(-5)^2-4\cdot 2\cdot 2=25-16=9\\ \\\sqrt{D}=3\\ \\u_{1,2}=\dfrac{-(-5)\pm 3}{2\cdot 2}=\dfrac{5\pm 3}{4}=2,\ \dfrac{1}{2}](https://tex.z-dn.net/?f=u%2B%5Cdfrac%7B1%7D%7Bu%7D%3D%5Cdfrac%7B5%7D%7B2%7D%5C%5C%20%5C%5C2u%5E2%2B2%3D5u%5C%20%5C%20%5B%5Ctext%7BMultiplied%20by%202u%7D%5D%5C%5C%20%5C%5C2u%5E2-5u%2B2%3D0%5C%5C%20%5C%5CD%3D%28-5%29%5E2-4%5Ccdot%202%5Ccdot%202%3D25-16%3D9%5C%5C%20%5C%5C%5Csqrt%7BD%7D%3D3%5C%5C%20%5C%5Cu_%7B1%2C2%7D%3D%5Cdfrac%7B-%28-5%29%5Cpm%203%7D%7B2%5Ccdot%202%7D%3D%5Cdfrac%7B5%5Cpm%203%7D%7B4%7D%3D2%2C%5C%20%5Cdfrac%7B1%7D%7B2%7D)
Now,
Answers: Weight - 7.62 pounds, Cost - $2.50
When we convert 3,456 grams into pounds, we get 7.62 pounds (rounded to the nearest hundredth). We can subtract the first pound off since we know that will cost $0.75 (7.62 - 1 = 6.62 pounds). Now we must round 6.62 up to 7 pounds and multiply that by the price for every pound or part of a pound (7 x 0.25 = $1.75). Now you combine both the cost of the initial pound and the cost of every pound or part of a pound over the first to get your final cost. ($0.75 + $1.75 = $2.50)
The equation out of this is; what is 250/100 of a number x = 90?
=> Division of 250 by 100 gives 2.5.
=> Now multiply 2.5 by a number x resulting to 2.5x on the L.H.S.
=> make x the subject and come up with x = 90/2.5.
answer is 1/36.
Answer:
The exact same as subtracting.
Example
5 + (-2) = 3
