SOLUTION: Hi. My problem is: Solve the linear system by using elimination So 7x - 4y = -30 3x + 4y = 10 I tried 7x

SOLUTION: Hi. My problem is: Solve the linear system by using elimination So 7x - 4y = -30 3x + 4y = 10 I tried 7x - 3�-2 3x.

Question 654294: Hi. My problem is: Solve the linear system by using elimination
So
7x - 4y = -30
3x + 4y = 10
I tried

7x - 3�-2
3x. -6 + 4y = 10
10x = -20 = (-2, ). +6. +6
4y = 16 / 4 = 4 ??? Am I performing this correct? Please help. Final answer is (-2,4)
Found 2 solutions by MathTherapy, lenny460:
Answer by MathTherapy(10552) (Show Source): You can put this solution on YOUR website!

Hi. My problem is: Solve the linear system by using elimination
So
7x - 4y = -30
3x + 4y = 10
I tried

7x - 3�-2
3x. -6 + 4y = 10
10x = -20 = (-2, ). +6. +6
4y = 16 / 4 = 4 ??? Am I performing this correct? Please help. Final answer is (-2,4)

No, you're not!!

7x - 4y = - 30 ---- eq (i)
3x + 4y = 10 ------ eq (ii)
10x = - 20 ----- Adding eqs (ii) & (i) to eliminate y and determine value of x

x = , or

7(- 2) - 4y = - 30 ----- Substituting - 2 for x in eq (i)
- 14 - 4y = - 30
- 4y = - 30 + 14
- 4y = - 16
y = , or

Send comments and �thank-yous� to �D� at MathMadEzy@aol.com
Answer by lenny460(1073) (Show Source): You can put this solution on YOUR website!
Hi. My problem is: Solve the linear system by using elimination
So
7x - 4y = -30
3x + 4y = 10
I tried

7x - 3�-2
3x. -6 + 4y = 10
10x = -20 = (-2, ). +6. +6
4y = 16 / 4 = 4 ??? Am I performing this correct? Please help. Final answer is (-2,4)

7x - 4y = -30 (eq1)
3x + 4y = 10 (eq2)

7x - 4y + 3x + 4y = -30 + 10
Combine like terms:
7x + 3x = 10x
-4y + 4y = 0
-30 + 10 = -20
Therefore:
10x = -20
Divide each side by 10
10x/10 = -20/10
x = -2

3x + 4y = 10 (eq2)
3(-2) + 4y = 10
-6 + 4y = 10
Add 6 to each side of the equation.
-6 + 4y + 6 = 10 + 6
Combine like terms:
-6 + 6 = 0
10 + 6 = 16
4y = 16
Divide each side by 4
4y/4 = 16/4
y = 4

Check:
7x - 4y = -30
7(-2) - 4(4) = -30
-14 - 16 = -30

Therefore:
The Answer:
x = -2 and y = 4

Lennox Obuong
Algebra Student
Email: obuong3@aol.com
RELATED QUESTIONS
solve the following by the elimination method 7x-4y=-30 and... (answered by Maths68)
7x-4y= -30 3x+4y=10 must be solved using... (answered by Alan3354)
Solve and check the following systems by elimination. Show steps. Check both equations. (answered by sophxmai)
solve the linear system by using elimination 3x - 4y = -16 x - 4y =... (answered by ewatrrr)
How to solve this linear system shown by using an elimination strategy: 5x - 4y= -3... (answered by MathLover1)
Solve by elimination 7x+5y=-12... (answered by checkley79)
Solve the linear system using elimination. x-2y=4... (answered by greenestamps,MathLover1)
Solve by the substitution method. 3x+2y=11 x-2=(-4y) what i did so far: x=2-4y... (answered by scott8148)
solve the equation system: 7x-47=-10 4y=x-2 (answered by checkley77)