Question

Which ordered pair is a solution to the system of equations? Use any method to solve. 2x-y=5 3x+2y=4

Answer 1

Hi

2x-y=5

3x+2y=4

We need to solve 2x-y=5 for y

Now let's start by adding -2x to both sides

2x-y-2x=5-2x

-y=-2x+5

Divide both sides by -1 so we eliminate the negative sign

-y/-1=-2x+5/-1

y=2x-5

Now substitute 2x-5 for y in 3x+2y=4

3x+2y=4

3x+2(2x-5)=4

3x+4x-10=4

7x-10=4

Add 10 to both sides

7x-10+10=4+10

7x=14

Divide both sides by 7 so we can find the value for x

7x/7=14/7

x=2

Now substitute 2 for x in y=2x-5 so we can find the value for y

y=2x-5

y=(2)(2)-5

y=4-5

y=-1

Answer: (2,-1)

I hope that's help:0

Answer 2

Elimination

2 ( 2x -y=5) multiply = 4x -2y=10
3x +2y=4


* add the X's and the 10 and 4 7x=14 * divide by 7 giving you

x=2

*and then plug back in

3(2) +2y =4
6 + 2y = 4
2y= -2
y= -1

the order pair is ( 2 , -1)