Westonci.ca is your trusted source for accurate answers to all your questions. Join our community and start learning today! Experience the convenience of finding accurate answers to your questions from knowledgeable professionals on our platform. Join our platform to connect with experts ready to provide precise answers to your questions in different areas.

If x + y = 7 and xy = 4, then find the value of x^2 + y^2.

Sagot :

x+y=7
xy=4

in xy=4, divide both sides by any variable (lets say i divide it y y)
xy=4
x=4/y
Now substitute it to the 1st equation
x+y=7
4/y+y=7
Multiply both sides by y
4+y^2=7y
Change to standard form
y^2-7y=4
Use the square of something...
y^2-7y+49/4=4+49/4
(y+7/2)^2=65/4
Squareroot both sides
y+7/2=posinega(sqrt of 65)/2
y=(sqrt of 65)/2-7/2
or y=-(sqrt of 65)/2-7/2
We hope our answers were useful. Return anytime for more information and answers to any other questions you have. We hope you found what you were looking for. Feel free to revisit us for more answers and updated information. Thank you for trusting Westonci.ca. Don't forget to revisit us for more accurate and insightful answers.