Math Question Please!?

Question

Use elimination to solve the system of equations given by -7x + 3y = 14 and 7x - 2y = -14.
Question 2..
Use elimination to solve the system of equations given by 10x - 40y = 60 and 15x + 40y = -10.
Thank You All!!

Answer 1

- 7x + 3y = 14- - - -- -Equatio 1
7x - 2y = - 14- - - - -Eqution 2
- - - - - - - - -
y = 0

The answer is y = 0

Insert the y value into euation 2

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7x - 2y = - 14

7x - 2(0) = - 14

7x - 0 = - 14

7x = - 14

7x/7 = - 14/7

x = - 14/7

x = - 2

The answer is x = - 2

Insert the x value into eqution 2

- - - - - - - - - - - - - - - - - - - - - -

7x - 2y = - 14

7(- 2) - 2(0) = - 14

- 14 = - 14

- - - - - - - - - - - -s-

Check for equation 1

- 7x + 3y = 14

- 7(- 2) + 3(0) = 14

- (- 14) + 0 = 14

14 = 14

- - - - - - - -

The solution set { - 2, 0 }

- - - - - - -s-

Answer 2

1) -7x+3y=14 + 7x-2y=-14 = 0x+1y=0 = y=0
-7x+3(0)=14 = -7x=14 = x=-2 + y=0

2) 10x-40y=60 + 15x+40y=-10 = 25x-0y=50 = x=2
15(2)+40y=-10 = 30+40y=-10 = 40y=-40 = y=-1 + x=2

Answer 3

-7x + 3y = 14
7x - 2y = -14 (Add)
-----------------
0 +y = 0
therefore y=0
-7x+3y =14
-7x = 14
x= 14/(-7)= -2

Question 2:
10x - 40y = 60
15x + 40y= -10 (Add)
--------------------
25x = 50
x=50/25 = 2
Substitute x in first equation
(10 * 2) - 40y=60
20 - 40y = 60
-40y= 60 - 20 = 40
y = 40/(-40)= -1

Answer 4

-7x+3y=14 (1)
7x-2y=-14 (2)

(1)+(2)
y=0
7x=-14
x=-2

solution:(-2,0)

10x-40y=60 (1)
15x+40y=-10 (2)
(1)+(2)
25x=50
x=2
2*10-40y=60
-40y=40
y=-1

solution: (2,-1)