Answer:
x = 14/3 + sqrt(217)/3 or x = 14/3 - sqrt(217)/3
Step-by-step explanation:
Solve for x:
x + 4 + 1/x = (10 x)/7
Bring x + 4 + 1/x together using the common denominator x:
(x^2 + 4 x + 1)/x = (10 x)/7
Cross multiply:
7 (x^2 + 4 x + 1) = 10 x^2
Expand out terms of the left hand side:
7 x^2 + 28 x + 7 = 10 x^2
Subtract 10 x^2 from both sides:
-3 x^2 + 28 x + 7 = 0
Divide both sides by -3:
x^2 - (28 x)/3 - 7/3 = 0
Add 7/3 to both sides:
x^2 - (28 x)/3 = 7/3
Add 196/9 to both sides:
x^2 - (28 x)/3 + 196/9 = 217/9
Write the left hand side as a square:
(x - 14/3)^2 = 217/9
Take the square root of both sides:
x - 14/3 = sqrt(217)/3 or x - 14/3 = -sqrt(217)/3
Add 14/3 to both sides:
x = 14/3 + sqrt(217)/3 or x - 14/3 = -sqrt(217)/3
Add 14/3 to both sides:
Answer: x = 14/3 + sqrt(217)/3 or x = 14/3 - sqrt(217)/3
Step-by-step explanation:
In order to use the elimination method, you have to create variables that have the same coefficient—then you can eliminate them. Multiply the top equation by 5. Now multiply the bottom equation by −3. Next add the equations, and solve for y.
I hope it's helpful!
Answer:
x = -1+✓17 or x = -1 -✓17
Step-by-step explanation:
x^2 + 2x + 1 = 17
Make the equation equal to 0 by taking away 17.
x^2 + 2x - 16 = 16
Put a, b and c into the quadratic formula.
a = 1 b = 2 c = -16
Answer:
The answer is 60
Step-by-step explanation:
It is 60 because x=2,so 9(2)+42=60
Answer: 9 telephones Hope this helps, please consider making me Brainliest.
Step-by-step explanation:
This is basically division, so 3 3/8 = 27/8.
27/8 divided by 3/8 = 9.
Therefore, Rob needs 9 telephones.
Hope this helps, please consider making me Brainliest.