Question

Help please! 99 Points!

Solve the system of equations using the Linear Combination Method.
5. 4x-9y=1
-4x+6y=-2

6. 3x-2y=14
2x+2y=6

Solve using any method
7. 4x+3y=29
5x+2y=24

8. -4x-2y=14
-10x+7y=-25

Answer 1

Hey there,

As seeing the (mathematics's above) I would be more willing list the steps, but to just tell you the answer.


`\boxed{y = -2.56}` and also
`\boxed{y =1.88}`

Hope this helps.

~Jurgen

Answer 2

Combination method: add the two equations together

5) 4x-9y=1 6) 3x - 2y = 14
+( - 4x+6y=-2 ) + (2x + 2y = 6)
---------------------- -------------------
0 - 5y = -1 5x + 0 = 20


-5y = -1 5x = 20

isolate the y isolate the x

-5y / -5 = -1/-5 5x/5 = 20/5

y = 1/5 x = 4

4x-9y=1 3x - 2y = 14
4x - 9(1/5) = 1 3(4) - 2y = 14
4x - 9/5 = 1 12 - 2y = 14
4x - 9/5 (+9/5) = 1 (+9/5) 12 (-12) - 2y = 14 (-12)
4x = 14/5 -2y = 2
4x/4 = 14/5(/4) -2y(/-2) = 2(/-2)
x = 14/20 y = -1


Elimination method

7) 4x + 3y = 29 + (5x + 2y = 24)
eliminate one of the variables by multiply the number to both sides

2 (4x + 3y = 29) + 3 (5x + 2y = 24)

8x + 6y = 58
-( 15x + 6y = 72)
----------------------
-7x = - 14
-7x/-7 = -14/-7

x = 2

4(x) + 3y = 29
4(2) + 3y = 29
3y + 8 = 29
3y + 8 (-8) = 29 (-8)
3y = 21
3y/3 = 21/3

y = 7


8) like #7, you must eliminate one of the variables by multiply the number to both sides

-4x - 2y = 14
-10x + 7y = -25

7(-4x - 2y = 14)
-2(-10x + 7y = -25)

-28x - 14y = 98
- (20x -14y = -25)
-----------------------
-48x = 123
-48x/-48 = 123/-48
x = -2.56

-4(-2.56) - 2y = 14
10.24 - 2y = 14
10.24(-10.24) - 2y = 14 (-10.24)
-2y = 3.76
-2y/-2 = 3.76/-2
y = -1.88







hope this helps