mATHs agenn ??

Question

solve these simutaneouse equations

1. 5 x - 4=4y
2y + 2 = x


2. 3 x + 8 y +24
x+y=3

plz show me the wrkings so i understand thank you xx

Answer 1

The first simultaneous equation is confusing. If you rearrange them to give this:
1.5x - 4 = 4y
x - 2 = 2y
(I just took the 2 across to the x side on the bottom equation then swapped the sides around so that it's easier to understand when compared with the top equation)
then you will see that if you were to multiply the bottom equation by 2 throughout and to keep the top equation the same, you would have:
1.5x - 4 = 4y
2x - 4 = 4y
Both of these have 4y on the right so it can be said:
1.5x - 4 = 2x - 4
Take 1.5x from 2x and -4 from -4:
0 = 0.5x
Divide by 0.5 throughout
0 = x

So now that x = 0, you can put this into either equation to work out a value for y - here's the bottom one again:
2y + 2 = x
We know x = 0 so:
2y + 2 =
Take 2 across
2y = -2
Divide by 2
y = -1
And so your answers are x = 0 and y = -1


Now onto the next one, I presume you mean that the top one is "x + 8y = 24"
x + 8y = 24
x + y = 3
What you can do here is take the bottom equation away from the bottom one (i.e take the x away from the x, the y away from the 8y and the 3 away from the 24) which gives you:
7y = 21
And so divide by 7 throughout
y = 3
Now you have y, you can look at the second equation again:
x + y = 3
We know that y = 3 so:
x + 3 = 3
Now if we take 3 from both sides we get:
x = 0
And so y = 3 and x = 0

I hope this is clear to you

Answer 2

First problem

equation (eq) 1 -> 5x - 4 = 4y
eq2 -> 2y +2 = x

(multiply eq 2 by 2) 4y + 2 = 2x
and rearrange to 4y = 2x - 2 make this eq3

Subtract eq3 FROM eq1 -> (5x - 4)- (2x - 4) = 4y - 4y
this makes 3x = 0
put this into eq1 -> -4 = 4y
therefore y=1, x=0


Problem 2->
eq1 -> 3x + 8y + 24 = 0
eq2 -> x+y = 3

Multiply eq2 by 3 giving;
eq3 -> 3x + 3y = 9

Subtract eq3 FROM eq1 -> (3x + 8y +24) - (3x +3y) = 9

this gives ; 5y + 24 = 9
therefore -> 5y = 9 - 24 = -15
so y = -3

Substitute in to eq2

x + (-3) = 3
so x = 0

therefore x=0, y=3

Answer 3

1/ First pair of equations
===================
1.5x-4=4y
2y+2=x

If 2y+2=x then x=2y+2 that's obvious.
This means you can replace "x" by (2y+2) everywhere you see an "x"

let's do that in the first equation: 1.5x-4=1.5(2y+2)-4
but 1.5x-4=4y so we have 1.5(2y+2)-4=4y

now let's remove this parentheses by multiplying its content by 1.5
We get 3y+3-4=4y
Which is the same as 3y-1=4y
but you see y on both side of the "=" we don't like that so let's get rid of the "y" on left side by subtracting 3y on both side
we get 3y-1-3y=4y-3y
which is the same as -1=y which means y=-1

BUT you know 2y+2=x which means 2(-1)+2=x
so we conclude x=-2+2=0

--> final solution y=-1 x=0

2/ Second pair of equations
====================
2.3x+8y+24
x+y=3

we need a x=something without any x
the second equation seems simpler so let's use it to get x=...
to convert "x+y" into "x" I need to subtract "y"
so we get x+y-y=3-y
We conclude x=3-y

now all you need to do is to replace "x" by "(3-Y)" in the fist equation to get 2.3(3-y)+8y+24 ??????

Hey this is NOT an equation!!! there is no "=" !!!
to have an equation you need an "=" somewhere!!!
So check your problem and solve it in the same as we did for the first equation

Answer 4

1. 5 x - 4=4y.......(1)
2y + 2 = x...........(2)

from (2),x=2y-2,now substitute into(1)
10y+10-4=4y
6y = -6
y= -1
substitute into (2)
-2+2=x
x= 0

2. 3 x + 8 y =24...(1)
x+y=3..................(2)

from (2), x=3-y

substitute into (1)
3(3-y)+8y=24
5y=15
y=3

substitute into (2)
x+3=3
x=0

i hope that this helps

Answer 5

in the first set, one of the variables, x, is already isolated. plug this value for 'x' into the first equation. this will give you: 1.5(2y+2) - 4 = 4y. simplifying this equation will give you 3y + 3 - 4 = 4y, simplifying further yields 3y - 1 = 4y. now move all the variables 'y' to the same side ==> -1 = y. now that you have a numerical value for 'y', plug it into either of the equations to give you the value for 'x'. doing this gives you y = -1, x = 0. now repeat these procedures for the second set of equations; isolate one variable, plug into the other equation, simplify this single variable equation to give a numerical value. plug this value into either equation and solve for the second variable. also, be sure to check that after you get both numerical values for the variables, plug them into both equations to make sure that it all works out.

Answer 6

Eh... neither... yet i wager i am going to pick English. I used to love English extra yet severe college made it boring. -_- yet I nonetheless love writing as a interest (and hate math, even although i'm not undesirable at it) so i am going to easily say English.

Answer 7

#1
5 x - 4=4y
2y + 2 = x

5x - 4y = 4
5(-x + 2y = -2)

5x - 4y = 4
-5x + 10y = -10

6y = -6
y = -1

5x - 4 = 4(-1)
5x - 4 = -4
5x = 0
x = 0

ANSWER
x = 0
y = -1

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

#2
3x + 8y = 24
x + y = 3

3x + 8y = 24
-3(x + y = 3)

3x + 8y = 24
-3x - 3y = -9

5y = 15
y = 3

3x + 8(3) = 24
3x + 24 = 24
3x = 0
x = 0

ANSWER
x = 0
y = 3

Answer 8

agenn? Is that like Pythagoras or something?

Answer 9

you should be doing your homework yourself