SOLUTION: Based on the lesson, which of the following would be the best approach for solving this system by substitution? 5x = y + 6 2x

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Question 555082: Based on the lesson, which of the following would be the best approach for solving this system by substitution?
5x = y + 6
2x - 3y = 4
Found 3 solutions by Alan3354, KMST, kkasko:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
Based on the lesson, which of the following would be the best approach for solving this system by substitution?
5x = y + 6
2x - 3y = 4
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I don't know what the lesson said, but I would solve the 1st eqn for y, and sub for y into the seoond one. No fractions that way.

Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website!
I do not know what the lesson said, but that system is begging you to solve equation for so you get "y = .." and then substitute the expression found for into equation
In substitution, the first step is to solve for x or for y in one of the equations. The espression you find is simpler if you solve for a variable whose coefficient is 1 or -1. Otherwise you may have to work with fractions, and mistakes are more likely.

Answer by kkasko(46)   (Show Source):
You can put this solution on YOUR website!
Based on the lesson, which of the following would be the best approach for solving this system by substitution?
5x = y + 6
2x - 3y = 4
Isolating the x value from the 5 by dividing it like this
5x=y+6
/5. /5. /5
x=1/5y+6/5
2x-3y=4
2(1/5y+6/5)-3y=4
2/5y+12/5-3y=4
Now collect like terms -3y+2/5y
-13/5y+12/5=4
-12/5. -12/5
-13/5y=8/5
Isolate the y
-13/5y=8/5
/(-13/5). /(-13/5)
y=-.6153846151. However we need to convert this into a fraction to get x so Math Fract
Y=-8/13
Now substitute it into the original equation
2x-3y=4
2x-3(-8/13)=4
Again can't have a decimal so math Fract
2x+24/13=4
Isolate 2x from -24/13 by adding 24/13 to 4
2x+24/13=4
-24/13. -24/13
Again math Fract
2x=28/13
Divide by 2
2x=(28/13)
/2. /2
Math Fract
x=14/13
CHECK
2x-3y=4
2(14/13)-3(-8/13)=4
4=4
Left hand side = Right hand side
Solution=(14/13,-8/13)

SOLUTION: Based on the lesson, which of the following would be the best approach for solving this system by substitution? 5x = y + 6 2x - 3y = 4