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HELP ME PLEASEEEEE

Solve the following system of equations using Substitution, showing all work.
y= 2x + 3
2x + 5y = 3


User Areum
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1 Answer

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Answer: (x,y) = (-1, 1)

This means that x = -1 and y = 1

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Step-by-step explanation:

The first equation says that y is the same as 2x+3

That allows us to substitute y for 2x+3 in the second equation like so:

2x+5y = 3

2x+5( y ) = 3

2x + 5(2x+3) = 3 .... y replaced with 2x+3

2x+10x+15 = 3

12x+15 = 3

12x = 3-15

12x = -12

x = -12/12

x = -1

Then we'll substitute this into the first equation to find y

y = 2x+3

y = 2(-1) + 3 .... x replaced with -1

y = -2+3

y = 1

Together x = -1 and y = 1 pair up to form the ordered pair solution (x,y) = (-1,1)

If you were to graph y = 2x+3 and 2x+5y=3 on the same xy grid, then you should see that the two lines intersect at the location (-1,1). This is a visual way to determine the solution quickly through use of a graphing calculator.

User Rhu
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