how to do subtitution method?

Question

y+x=7
y+3=x

Answer 1

Substitution methods, mean plugging in the other formula.
Let see

1. y+x=7
2. y+3=x

So for number 2 you can do --> subtract 3 to the other side and it will equal y=x-3

Then you plug the new equation to equation number one, when you see y so it would be (x-3)+x=7
andd...2x-3=7
add 3 to both side, and it would be 2x=10
divde by 2, x = 5
now to find the y value
plus the value for x for the first equation >>y+(5)=7
subtract 5 at both side
y=2
now we check

1. 5+2=7 check!
2. 2+3=5 check!!
Correctt.. LOl

Answer 2

y + x = 7- - - - - Equatiion 1
y + 3 = x- - - - - Equation 2
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Substitute method equation 2

y + 3 = x

y + 3 - 3 = x - 3

y = x - 3

The answer is y = x - 3

Insert they value into equation 1

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y + x = 7

x - 3 + x = 7

2x - 3 = 7

2x - 3 + 3 = 7 + 3

2x = 10

2x/2 = 10/2

x = 5

The answer is x = 5

Insert the x vallue into equation 1

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y + x = 7

y + 5 = 7

y + 5 - 5 = 7 - 5

y = 2

The anser is y = 2

Insert the y value into equation 1

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Check for equation 1

y + x = 7

2 + 5 = 7

7 = 7

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Check for euation 2

y + 3 = x

2 + 3 = 5

5 = 5

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The solution set is { 5, 2 }

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Answer 3

Take the second equation and substitute it into the first equation:
y+y+3=7
2y+3=7
2y=4
y=2

2+3=x
x=5

The solution set is (5,2)

Check:
2+5=7
7=7

2+3=5
5=5

Answer 4

y+x=7

y+3=x substitute this for x in the equation above

y+(y+3)=7
2y+3=7
2y=4
y=2 substitute this in the 2nd equation
y+3=x
2+3=x
x=5

(5, 2)

Answer 5

In the substitution method, you substitute one thing for another. Since we know that x = y + 3, let's substitute that into the other equation.

y + (y + 3) = 7
2y + 3 = 7
2y = 4
y = 2

So x = 5. You can check by putting those values for x and y into both equations.

Answer 6

to do substitution mean put the value of the variable that has been given into the first equation.

y+x=7....(i)
x=y+3.....(ii)

put the (ii) into (i) as the value of x.
y+y+3=7
2y+3=7
2y=7-3
2y=4
2y/2=4/2
y=2

to find x put 2 where ever you see y in the (i) equation.
y+x=7 ...(i)
2+x=7
x=7-2
x=5.
remember that you can substitute the value of y into any of the two equation,but when you have a negative sign in one try to avoid that
good luck.

Answer 7

y+x=7
y+3=x

x + y =7(1)
x - y =3(2)

x + y =7
2x = 10 ( (1) + (2) )

x = 5
y = 2

Answer 8

y+x = 7 ---- (i)
y+3 = x ---- (ii)

from equation (ii), substitute the value of x in equation (i)

=> y+(y+3) = 7
=> 2y+3 = 7
=> 2y = 4
=> y = 2

now, substitute this value of y in equation (ii)

=> 2+3 = x
=> 5 = x