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Question 1018666: NEED ANSWERS ASAP SHOW WORK PLEASE I KNOW ITS LONG BUT PLEASE I REALLY NEED IT RIGHT NOW
1. Solve and verify each of the following systems of linear equations.
/3 a. 5x – 2y =- 6 and 2x – y = 1
Answer:
/3 b. 2x + 3y = 432 and 5x – 2y = 16
Answer:
2. Lena thinks she has found a shortcut for solving some linear systems. Her solution to the ystem 4y = 3x + 7 and 9x + 4y – 139 = 0 is shown.
/1 a. Is Lena’s method correct?
Answer:
/1 b. If Lena’s method is correct, explain it. If it is incorrect, describe her error.
Answer:
3. The numbers x and y have a sum of 1 and a difference of 11.
/1 a. Write a system of equations to represent this information.
Answer:
/2 b. Solve the system of equations to determine the numbers.
Answer:
Answer by richard1234(7193)   (Show Source):
You can put this solution on YOUR website! 1a. One way to solve is to rearrange the second equation to y = 2x-1. Substitute the expression for y into the first equation to get 5x - 2(2x-1) = -6, or x + 2 = -6 Then x = -8. Since y = 2x-1, we have y = 2(-8) - 1 = -17. You can check that (x,y) = (-8,-17) works.
1b. You can solve this one a similar way. Remember you can multiply or divide equations by a nonzero constant to produce an equivalent equation, and you can add two equations to produce an equation. For example, you could divide the second equation by 2.
2. Cannot solve; you didn't provide Lena's solution
3a. x+y = 1, x-y = 11
3b. I will leave it to you to solve. You can use substitution, but a faster way might be to add the equations together.
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