SOLUTION: x+y=2 2x+7y=9

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Question 176283This question is from textbook McDougal Littell MATH
: x+y=2
2x+7y=9 This question is from textbook McDougal Littell MATH

Found 3 solutions by EMStelley, jojo14344, MathTherapy:
Answer by EMStelley(208) About Me  (Show Source):
You can put this solution on YOUR website!
Let's solve this one with the addition method. I will multiply the first equation by -2 to obtain the following system:
-2x-2y=-4
2x%2B7y=9
Now, adding the two together, we get:
5y=5
So y=1. To find x, we just plug in y=1 to either equation.
x%2B1=2
So x=1. Thus the solution is (1,1).

Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!

Line Equations:
x%2By=2, EQN 1
2x%2B7y=9, EQN 2
In EQN 1, we get:
y=2-x, EQN 3 ------> subst. in EQN 2:
2x%2B7%282-x%29=9
2x%2B14-7x=9, combine similar terms
14-9=7x-2x
5=5x------>cross%285%291%2Fcross%285%29=cross%285%29x%2Fcross%285%29
highlight%28x=1%29, subst. in EQN 3:
y=2-1
highlight%28y=1%29
We'll see the graph:
----> Point of Intersection (1,1), RED>>EQN1; GREEN>>EQN2
Thank you,
Jojo

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
-2(x + y = 2)
2x + 7y = 9
- 2x - 2y = - 4
5y = 5
y = 1
x + 1 = 2
x = 1
Solution: (1, 1)