SOLUTION: We are soing an Alg. 1 review to start off Alg. 2 and after 2 years i forgot almost everything about algebra. Our teacher wants us to "Use elimination to solve"
5x+2y=5
3x+y=2
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5x+2y=5
3x+y=2
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Question 49595: We are soing an Alg. 1 review to start off Alg. 2 and after 2 years i forgot almost everything about algebra. Our teacher wants us to "Use elimination to solve"
5x+2y=5
3x+y=2 Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website! Perhaps a refresher course in Algebra I is in order.
Use "elimination" to solve:
1)
2)
You have here what is called a "system of equations" In this case, two equations in two unknowns. You can't solve these directly, so what you have to is to "eliminate" one of the unknowns (variables x, y) then solve for the remaining variable. How do you "eliminate" one of the variables? In this problem, you want to change one of the equations so that both equations will have the same number of x's or y's. You can do this by multiplying equation 2) by 2. Once you've done that, then you will subtract one equation from the other to eliminate the y-variable. Watch!
Multiply equation 2) by 2.
1)
2a) Now subtract equation 1) from equation 2a) to get: Now that you have the value for x, you can substitute this into either of the two original equations to solve for y. Let's use equation 2).
2) Substitute x = -1 and solve for y.
2b) Simplify. Add 3 to both sides.
The solution is: (-1, 5)
This means that if you were to graph these two linear equations on the same coordinate grid sheet, the two lines would intersect at the point (-1, 5). The graph below illustrates this:
(