Home › NY Regents Algebra I › Mathematics › Systems of Linear Equations › Solve by elimination: x + y = 10 and x - y = 12.
Solve by elimination: x + y = 10 and x - y = 12.
A(-1, 11)
B(11, 1)
C(1, 11)
D(11, -1)
Answer & Solution
Correct answer: D. (11, -1)
1. Both equations are in standard form, and the coefficients of y are already opposites.
2. Add the two equations to eliminate y: 2x equals 22, so x equals 11.
3. Substitute x = 11 into x + y = 10 to get y equals -1.
4. Check: 11 plus -1 equals 10, and 11 minus -1 equals 12, so (11, -1) satisfies both equations.
_Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 5 "Systems of Linear Equations", section 5.3 Solve Systems of Equations by Elimination_
Related questions
The perimeter of a rectangle is 40. The length is 4 more than the width. Find the length aThe sum of two numbers is 10. One number is 4 less than the other. Find the numbers.When Jenna spent 10 minutes on the elliptical and 20 minutes on circuit training, she burnA married couple together earns $110,000 a year. The wife earns $16,000 less than twice whDevon is 26 years older than his son Cooper. The sum of their ages is 50. Find their ages.In the seven-step Problem Solving Strategy for Systems of Linear Equations, what is Step 4Joe had one medium fries and two small sodas for 620 calories on Monday, and two medium frThe sum of two numbers is 39. Their difference is 9. Find the numbers.