SOLUTION: Solve this system using the Substitution Method: x + y = 7/2 4x - 3y = -14

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Question 190108: Solve this system using the Substitution Method:
x + y = 7/2
4x - 3y = -14
Answer by cutepiscean5(19) About Me  (Show Source):
You can put this solution on YOUR website!
Substitution method---

From the first equation take out one variable in terms of the other and substitute it in the other equation.
we have:
+x+%2B+y+=+7%2F2+
=> +x+=+7%2F2+-+y+
Now, substitute this value of x, into equation 2.
+4x+-+3y+=+-14+
=> +4%2A%287%2F2+-+y%29+-+3y+=+-14+ (Now, use distributive law to open the brackets)
=> +14+-+4y+-+3y+=+-14+
=> +14+-+7y+=+-14+ (Next, bring -14 to the Left hand side by adding both sides by 14 and bring -7y to the Right hand side by adding both sides by 7y)
=> +14+%2B+14+=+7y+ (Next, Re-arrange the equation)
=> +7y+=+14+%2B+14+
=> +7y+=+28+
=> +y+=+28%2F7+
=> +highlight%28y+=+4%29+
plug back this value of y into the value of x to obtain x.
=> +x+=+7%2F2+-+y+
=> +x+=+7%2F2+-+4+
=> +highlight%28x+=+-1%2F2%29+
hope this helps.