Question

solve using substitution or the linear combination/elimination method 5x-25y=40
x=4y+6 thx

Answer 1

x=4y+6
5(4y+6)-25y=40
20y+30-25y=40
-5y=10
y=-2

Answer 2

that solved for y now substitute the y value in either equation and solve for x. Then check answer.

Answer 3

thanks what method did you use?

Answer 4

I used the substitution method.

Answer 5

In the 2nd line you will note that the x has been substituted with 4y+6/

Answer 6

Looking at the 2nd equation,x=4y+6 is a good one to use to solve for x
x=4(-2)+6=-2..........my goodness they are both -2. Better check and verify.
-2= -8+6
-2=-2 thats good, now for the first one 5(-2) -25(-2)=40
-10+50=40
40=40 good, it is correct.

Answer 7

be back in a few

Answer 8

thank you for checking sir, I came up with that answer also and I appreciate you double checking.

Answer 9

ok thank you could you please help me with this one:7x+2y=10 3x-5y=-25

Answer 10

I'm back, you still here.

Answer 11

yes

Answer 12

Is there a preference in the method to use to solve the new problem?

Answer 13

either substitution or the linear combination/elimination method thank you for asking

Answer 14

I will use the elimination method, to you this method, you want to get one of the variables ( x or y) to have equal and opposite coefficients. I choose to eliminate the y to do that I must multiply all terms in the first equation by this will give me:
21x+6y=30. Now I multiply 2nd equation by a -7 (all terms) getting:
-21x +35y=175 I now add the two equations and eliminate the x
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41y=205
y=5 we now solve for x by subsstituting the value of y in your equation, either one.

Answer 15

*eliminate the "x"
made a typo

Answer 16

would x =0 ?

Answer 17

Lets see.. I will use 7x+2y=10
7x + 2(5)=10
7x=0
x=0 Yes you're correct.

Answer 18

thank you, I am trying to study for a semester exam, would you be willing to help me with a few more? I really appreciate your help

Answer 19

I will have to run, Thurs night is my TV night lol, Missing, Person of Interest, and The Mentalist.

Answer 20

Post again, there is usually someone to help.

Answer 21

ok thank you

Answer 22

Good luck with the semester exam, I feel that you are going to do OK on that exam.

Answer 23

alright i appreciate your help