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please, I will be waiting for the solution. Wasn't good in maths. elimination of substitution method

naturalwaves see this

Use substitution method

Swissheart:
naturalwaves see this

Thanks a lot I appreciate, she is submitting tomorrow. The questions are 5.

AJOBI77:
Use substitution method

Bros I don't know, please help or mention someone who can, this must be solved this night.

cc fynestboi

for Number 5

Solution

F - 2g = -3
2f - 3g = 1-2

Using Elimination Method

Mutiply eqn 1 by 2 and eqn 2 by 1

=> F - 2g = -3 ----- x 2

2F - 3g = -1 ------ x 1

This will give us

2F - 4g = -6

2F - 3g = -1

Subtract eqn 2 from eqn 1

==> -g = - 5

divide both sides by -

==> g = 5

Substitute g = 5 in eqn 1

2F - 4 (5) = -6

2F - 20 = -6

2F = -6 + 20

2F = 14

F = 14/2

F = 7.



FOR QUESTION 4

Typing...

generalbush:
for Number 5

Solution

F - 2g = 13
2f - 3g = 1-2

Using Elimination Method

Mutiply eqn 1 by 2 and eqn 2 by 1

=> F - 2g = -3 ----- x 2

2F - 3g = -1 ------ x 1

This will give us

2F - 4g = -6

2F - 3g = -1

Subtract eqn 2 from eqn 1

==> -g = 5

Substitute g = 5 in eqn 1

2F - 4 (5) = -6

2F - 20 = -6

2F = -6 + 20

2F = 14

F = 14/2

F = 7.

You didn't get the question right. please check again.

Sirgay:
You didn't get the question right. please check again.

But I already cross checked. It gave me a balanced equation.

generalbush:
But I already cross checked. It gave me a balanced equation.

There was no 13 in the question, please check again.

Sirgay:
There was no 13 in the question, please check again.

Mistake.I wanted to type "-3"

I will edit the question.

generalbush:
Mistake.I wanted to type "-3"
I will edit the question.

Ok please carry on

Sirgay:
Ok please carry on

For question 1

[s][/s]

X/1 - Y/2 = 1 -------------- eqn 1

Removing equations, we will multiply all sides by 2

2(x/1) - 2(y/2) = 2 * 1

This will give us...

2x - y = 2 ----- Eqn 1


Solving eqn 2...

x/2 + y/3 = 17/6

Multiplying both sides by 6, it gives us...

6 * x/2 + 6* y/3 = 6 * 17/6

==> 3x + 2y = 17 ---- Eqn 2

Combining both equations...

2x - y = 2

3x + 2y = 17

Using Elimination method, I multiply eqn 1 by 2 and eqn 1 by 1

It gives me ==> 2* 2x - 2*y = 2*2
1* 3x + 1* 2y = 1* 17


It gives us...

4x - 2y = 4

3x + 2y = 17

Subtracting eqn 2 from 1

It gives us...

7x = 22

x= 22/7

Substituting x = 22/7 in eqn 1, we have

2 (22/7) - y = 2

44/7 - y = 2

Multiply all sides by 7

7* 44/7 - 7*y = 7*2

==> 20 -7y = 14

- 7y = 14 - 44

-7y = -30

Divide both sides by -

y = 30/7

generalbush:
For question 1
[s][/s]
X/1 - Y/2 = 1 -------------- eqn 1
Removing equations, we will multiply all sides by 2
2(x/1) - 2(y/2) = 2 * 1
This will give us...
2x - y = 2 ----- Eqn 1

Solving eqn 2...
x/2 + y/3 = 60/6
Multiplying both sides by 6, it gives us...
6 * x/2 + 6* y/3 = 6 * 60/6
==> 3x + 2y = 60 ---- Eqn 2
Combining both equations...
2x - y = 2
3x + 2y = 60
Using Elimination method, I multiply eqn 1 by 2 and eqn 1 by 1
It gives me ==> 2* 2x - 2*y = 2*2 1* 3x + 1* 2y = 1*6

It gives us...
4x - 2y = 4
3x + 2y = 6
Subtracting eqn 2 from 1
It gives us...
7x = 10
x= 10/7
Substituting x = 10/7 in eqn 1, we have
2 (10/7) - y = 2
20/7 - y = 2
Multiply all sides by 7
7* 20/7 - 7*y = 7*2
==> 20 -7y = 14
- 7y = 14 - 20
-7y = -6
Divide both sides by -
y = 6/7

Thanks generalbush, I can't thank you more about

generalbush please check how you got 60/6 (60 over 6) the improper fraction or something, isn't there an error?

Sirgay:
please, I will be waiting for the solution. Wasn't good in maths. elimination of substitution method

change all the equation to non-fractional linear equation for question 1 and 2.

for question 1, multiply eqn (i) by 2 and eqn (ii) by 6

for question 2, multiply eqn (i) by 2 and eqn (ii) by 6

dejt4u:
change all the equation to non-fractional linear equation for question 1 and 2.

for question 1, multiply eqn (i) by 2 and eqn (ii) by 6

for question 2, multiply eqn (i) by 2 and eqn (ii) by 6

please help me with that. I can't am too old for maths lesson.

generalbush will 2 whole number 5 0ver 6 gives us 60 over 6 in that question one solution? please check.

Sirgay:
generalbush will 2 whole number 5 0ver 6 gives us 60 over 6 in that question one solution? please check.

Nop.

generalbush:
Nop.

I know that must be an error, thanks for confirming it.

Just download photomath from play store and scan ( via your phone camera) or type your questions then safe your self the stress of coming here. Life has been made easier in this generation.

Sirgay:
I know that must be an error, thanks for confirming it.

I will edit now.

I have edited it

Sirgay:
I know that must be an error, thanks for confirming it.

Please edit the wrong answers you quoted. So that it won't confuse Op

generalbush:
Please edit the wrong answers you quoted. So that it won't confuse Op

Ok

generalbush:
for Number 5

Solution

F - 2g = -3
2f - 3g = 1-2

Using Elimination Method

Mutiply eqn 1 by 2 and eqn 2 by 1

=> F - 2g = -3 ----- x 2

2F - 3g = -1 ------ x 1

This will give us

2F - 4g = -6

2F - 3g = -1

Subtract eqn 2 from eqn 1

==> -g = - 5

divide both sides by -

==> g = 5

Substitute g = 5 in eqn 1

2F - 4 (5) = -6

2F - 20 = -6

2F = -6 + 20

2F = 14

F = 14/2

F = 7.



FOR QUESTION 4

Typing...

This is wrong. You supposed to equate both the first and second terms to 1. Like...

F - 2g +3= 1
2f - 3g +2= 1
Which will gives
F-2g=-2...........(1)
2f-3g=-1...........(2)
Multiplying (1) by 2 gives
2f-4g=-4.......(3)
2f-3g=-1.......(2)
Subtracting eqn (2) from the (3) gives
-g=-3
g=3
Substitute for g in equation 1
F-2g=-2
F-2(3)=-2
F-6=-2
F=-2+6
F=4

generalbush:
For question 1
[s][/s]
X/1 - Y/2 = 1 -------------- eqn 1
Removing equations, we will multiply all sides by 2
2(x/1) - 2(y/2) = 2 * 1
This will give us...
2x - y = 2 ----- Eqn 1

Solving eqn 2...
x/2 + y/3 = 17/6
Multiplying both sides by 6, it gives us...
6 * x/2 + 6* y/3 = 6 * 17/6
==> 3x + 2y = 17 ---- Eqn 2
Combining both equations...
2x - y = 2
3x + 2y = 17
Using Elimination method, I multiply eqn 1 by 2 and eqn 1 by 1
It gives me ==> 2* 2x - 2*y = 2*2 1* 3x + 1* 2y = 1* 17

It gives us...
4x - 2y = 4
3x + 2y = 17
Subtracting eqn 2 from 1
It gives us...
7x = 22
x= 22/7
Substituting x = 22/7 in eqn 1, we have
2 (22/7) - y = 2
44/7 - y = 2
Multiply all sides by 7
7* 44/7 - 7*y = 7*2
==> 20 -7y = 14
- 7y = 14 - 44
-7y = -30
Divide both sides by -
y = 30/7

You are wrong the answer is Y = 4 X = 3

Sirgay:
Ok

Solution to Q1


Edited.. Answer to Q1 is x = 3 and y = 4

Answer to Question 2

...

Solution to Question 3

Solution to Question 4

[/quote][/color]

generalbush:
For question 1

[s][/s]

X/1 - Y/2 = 1 -------------- eqn 1

Removing equations, we will multiply all sides by 2

2(x/1) - 2(y/2) = 2 * 1

This will give us...

2x - y = 2 ----- Eqn 1


Solving eqn 2...

x/2 + y/3 = 17/6

Multiplying both sides by 6, it gives us...

6 * x/2 + 6* y/3 = 6 * 17/6

==> 3x + 2y = 17 ---- Eqn 2

Combining both equations...

2x - y = 2

3x + 2y = 17

Using Elimination method, I multiply eqn 1 by 2 and eqn 1 by 1

It gives me ==> 2* 2x - 2*y = 2*2
1* 3x + 1* 2y = 1* 17


It gives us...

4x - 2y = 4

3x + 2y = 17

Subtracting eqn 2 from 1

It gives us...

7x = 22

x= 22/7

Substituting x = 22/7 in eqn 1, we have

2 (22/7) - y = 2

44/7 - y = 2

Multiply all sides by 7

7* 44/7 - 7*y = 7*2

==> 20 -7y = 14

- 7y = 14 - 44

-7y = -30

Divide both sides by -

y = 30/7

Check the solution again
17+4 is 21... Therefore x=7