algrebra pleeease anyone help?

3x + 4y = 12
y = -2x + 10

Since y = -2x + 10 (second equation), substitute this into the first equation, i.e.,

3x + 4(-2x + 10) = 12

Simplifying the above,

3x - 8x + 40 = 12

-5x = 12 - 40

-5x = -28

x = 28/5

Follow the same procedure in the second problem and you will be OK.

Hope this helps.

plug in y into both equations, find like terms, move everything to the other side, and get x.

3x + 4(-2x+10) = 12
3x + -8x + 40 = 12
-5x = -28
x = 28/5

4x + 9(-1/3x + 2) = 24
4x + -3x + 18 = 24
1x = 6
x=6

Question 1
3x + 4(-2x + 10) = 12
3x - 8x + 40 = 12
- 5x = - 28
x = 28/5

y = - 56/5 + 50/5
y = - 6/5

x = 28/5 , y = - 6/5

Question 2
4x - 3x = 24
x = 24

y = - 8 + 2
y = - 6

x = 24 , y = - 6

1) subsitute the value of y into the equation
3x+4(-2x+10)=10
3x+(-8x+40)=10
3x-8x+40=10

simplify equation
-5x+40=10

subtract 40 to other side
-5x=-30

divide by -5
x=6

2) do the same as above
4x+9(-1/3x+2)=24
4x+(-3x+18)=24
4x -3x+18=24
x+18=24
x=6

1)
3x + 4y = 12 (solve by using substitution))
y = -2x + 10

3x + 4y = 12
3x + 4(-2x + 10) = 12
3x - 8x + 40 = 12
-5x = 12 - 40
-5x = -28
x = -28/-5
x = 28/5 (5.6)

y = -2x + 10
y = -2(28/5) + 10
y = -56/5 + 50/5
y = -6/5 (-1.2)

∴ x = 28/5 (5.6) , y = -6/5 (-1.2)

= = = = = = = =

2)
4x + 9y = 24
y = -1/3(x) + 2

y = -1/3(x) + 2
y = -x/3 + 2

4x + 9y = 24
4x + 9(-x/3 + 2) = 24
4x - 3x + 18 = 24
x = 24 - 18
x = 6

y = -1/3(x) + 2
y = -6/3 + 2
y = -2 + 2
y = 0

∴ x = 6 , y = 0

1. 3x+4y=12
....y= -2x+10

3x+4(-2x+10) = 12 plug the 2nd equation into the first equation to solve
3x-8x+40= 12 multiply using the distributive property
-5x+40= 12 combine like to terms.
.......-40...-40 subtract 40 from each side
-5x= -28
x= 5.6

y= -2x+10
y= -2(5.6)+10 plug the answer for x into an original equation
y= -11.2 + 10 add together
y = -1.2

x = 5.6, y = -1.2

2) 4x+9y= 24
......y = -1/3x+2

4x+9(-1/3x+2) = 24 plug in the 2nd equation into the 1st equation similar to what i did in the first problem

4x-3x+18= 24 use the distributive property to multiply
1x+18=24 combine like terms
.....-18..-18 subtract 18 from both sides
x= 6

y= -1/3x+2
y= -1/3(6) +2 to solve for y plug in the answer for x into one of the original equations

y = -2+2
y=0

x=6, y=0

hope to have helped

1.) 3x + 4y = 12
y = -2x + 10

lets sub the second equation into the first

3x + 4( -2x + 10) = 12
3x -8x + 40 = 12
-5x = -28
x = 5.6

y = -2x + 10
y = -2(5.6) + 10
y = -1.2

2.) 4x + 9y = 24
y = -1/3x + 2

the same here. lets do some subs, the second into the first one

4x + 9y = 24
4x + 9 (-1/3x + 2) = 24
4x - 3x + 18 = 24
x = 6

y = -1/3x + 2
y = -2 + 2
y = 0

1.) 3x + 4y = 12 .......(1)
y = -2x + 10 or 2x+y = 10 .......(2)
Multiplying equation (2) with 4 to make coeffiecient of y in both equal
8x+4y = 40 ........(3)
subtracting (1) from (3)
8x - 3x = 40 - 12
5x = 28
x=28/5 = 5.6
Substituting x= 5.6 in equation (2)
2*5.6 + y = 10
11.2+y=10
y = 1.2
So, x = 5.6 and y = 1.2 is the solution

2.) 4x + 9y = 24 ......(1)
y = -1/3x + 2 or 3y = -x +6 or x+3y = 6 .......(2)
Multiplying equation (2) with 3 to make coeffiecient of y in both equal
3x +9y = 18 .........(3)
Subtracting equation (1) from (3)
4x - 3x = 24 - 18
x = 6
Substituting x = 6 in equation (1)
4*6 + 9y = 24
9y = 0
y = 0
So, x = 6 and y = 0 is the solution

1) you want the first part to be moved into y=mx+b format:

so subtract 3x from both sides, 4y= -3x+ 12
now to get y alone divide all parts by 4, which gives you
y= -3/4x + 3.......

(about the second part, are these equations equal to each other?, what exactly do you need to do with them?

2. again, the first thing you want to do is get y=mx+b format:
4x+ 9y= 24, subtract 4x; 9y= -4x+24 divide by 9 to get y alone

y= -4/9x + 24/9

et cetera.

again, what exactly do you need done with these other equation?
i.e. do you need to see if they're parallel? are they equal? do you need the third side to a triange? etc.

1 4y+8x=40
-( 3x+4y=12)
5x=28
x=5.6 y=-1.2
2 4x+9y=24
-(9y+3x=18)
x=6
y=0