SOLUTION: I really need your help in solving this problem. Your time and efforts will be very much appreciated. Here is the question? Solve each system by substitution: (2x + y = - 7 (y

Algebra ->  Linear-equations -> SOLUTION: I really need your help in solving this problem. Your time and efforts will be very much appreciated. Here is the question? Solve each system by substitution: (2x + y = - 7 (y       Log On


   



Question 914458: I really need your help in solving this problem. Your time and efforts will be very much appreciated. Here is the question? Solve each system by substitution:
(2x + y = - 7
(y = 3x + 8

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

2x+%2B+y+=+-+7 .........eq.1
y+=+3x+%2B+8 ...........eq.2....substitute y in eq.1
_____________________________________
2x+%2B+%283x+%2B+8%29+=+-+7 .........eq.1...solve for x
2x+%2B+3x+%2B+8+=+-+7
5x=+-+7-8
5x=+-15
x=+-15%2F5
highlight%28x=+-3%29
go back to eq.2,substitute x and solve for y

y+=+3%28-3%29+%2B+8 ...........eq.2....

y+=+-9+%2B+8
highlight%28y+=+-1%29
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-2x-7%2C+3x+%2B+8%29+