simultaneous equations substition methos help?

That's so easy!

Take 2x-y=10 as equation 1 and take y=10-3x as equation number 2.

Since y=10-3x,substitute equation number 2 into equation number 1.

That is:2x-(10-3x)=10
2x-10+3x=10
2x+3x=10+10
5x=20
Therefore,x=4.

Now that you have found x,now substitute x=4 into equation 2.
That is:y=10-3(4)
Therefore, y=-2.

So your final answer is x=4 and y=-2!

Hope this helps!

Relative value of y (1st equation):
2x - y = 10
y = 2x - 10

Value of x:
2x - 10 = 10 - 3x
5x = 20
x = 4

Value of y:
= 2(4) - 10
= 8 - 10
= - 2

Answer: x = 4, y = - 2

Proof (1st equation):
2(4) - (- 2) = 10
8 + 2 = 10

Proof (2nd equation):
- 2 = 10 - 3(4)
- 2 = 10 - 12
- 2 = - 2

2x - (10 - 3x) = 10
2x - 10 + 3x = 10
5x = 20
x = 4

y = 10 - 12
y = - 2

x = 4 , y = - 2

Place the second equation into the 1 st equation like this

2x - (10-3x) = 10 then you solve for x
2x -10 + 3x =10
5x -10 = 10
5x =20
x =20/5 =4 then u going back and find y by substituting it in the 2nd equation.

y=10-3(4)= 10-12= -2

therefore we can conclude the these 2 with intersect at the point (4,-2)

2x - y = 10
y = 2x - 10

y = 10 - 3x
2x - 10 = 10 - 3x
2x + 3x = 10 + 10
5x = 10
x = 10/5
x = 4

2x - y = 10
2(4) - y = 10
8 - y = 10
y = 8 - 10
y = -2

∴ x = 4 , y = -2

2x-y=10
y = -10 + 2x



y=10-3x

-10 + 2x = 10-3x
5x = 20
x = 4


since y = 10 -3x
y = 10- 12
y = -2


solutionL
x = 4
y = -2

2x-y=10 ; y=2x-10

subtitute to y of the 2nd equation....

2x-10=10-3x
2x+3x=10+10
5x=20
x=4 ;
so..
2x-y=10 -->> 2(4)-y=10
8-y=10
8-10=y
-2=y


there..

2x - (10 - 3x) = 10
2x - 10 + 3x = 10
5x - 10 = 10
5x = 20
x = 4

y = 10 - 3(4)
y = 10-12
y = -2

(4, -2)

2x-10+3x=10
5x=20
x=4