2x^2-4x+y=3 and 4x-2y=-7
in Pre-Algebra Answers by

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.

1 Answer

solve the 2nd equation for y, get y=2x+(7/2)

then plug that into the 1st equation for y and get 2x^2 - 4x + (2x +(7/2)) =3

Combine like terms on the left and subtract 3 from both sides to get

2x^2 - 2x +1/2 = 0, if you don't like working with fractions you can multiply it all by 2 and get 4x^2 - 4x +1 =0

then factor into (2x-1)(2x-1)=0, set 2x-1=0 and solve to get x=1/2, plug x=1/2 into either equation to get y= 4 1/2

solution set is (1/2, 4 1/2)
by Level 5 User (11.9k points)

Related questions

1 answer
asked Feb 14, 2012 in Algebra 1 Answers by anonymous | 736 views
1 answer
asked Apr 4, 2018 in Algebra 1 Answers by Joahua | 385 views
1 answer
asked Apr 10, 2013 in Algebra 2 Answers by anonymous | 838 views
1 answer
asked Jan 30, 2012 in Algebra 2 Answers by maria15 Level 1 User (180 points) | 782 views
1 answer
asked Jan 30, 2012 in Algebra 2 Answers by maria15 Level 1 User (180 points) | 743 views
1 answer
Welcome to MathHomeworkAnswers.org, where students, teachers and math enthusiasts can ask and answer any math question. Get help and answers to any math problem including algebra, trigonometry, geometry, calculus, trigonometry, fractions, solving expression, simplifying expressions and more. Get answers to math questions. Help is always 100% free!
87,516 questions
100,285 answers
2,420 comments
734,483 users