Help needed very badly please?

Question

Solve the system by addition
5x - 4y = -5
x - 2y = -7

Answer 1

x= 2y -7
5(2y-7) -8y =5
10y-35 -4y = 5
6y = 40
y=40/6

x=2(40/6) -7
x=80/6 -42/6
x=38/6

Answer 2

Solve for x first in the simplest equations:
x - 2y = -7 ===> x = -7 + 2y

Then Plug this equation in for x in the remaining equation

5x - 4y = -5 ====> 5(-7+2y) - 4y = -5 ===> -35 + 10y - 4y = -5

-35 + 6y = -5 ====> 6y = 30 ===> y = 5

Then plug a 5 in for y and solve for x in the original equation:

x - 2(5) = -7 ==> x - 10 = -7 ===> x = 3

Answer 3

you add the xs, ys and answer vertically then you can get the x and y values from there. this is what the problem comes out to be i think.
6x - 6y = -12

then to figure the x value it would be 6x / 6= -12 / 6+6y / 6, so x = -2 + y.

then you have to substitute that in for x in one of the formulas given, i beleive, so, well use the second one and it would look like this, -2 +y -2y = -7

solve from there and it should look like this, -y = -5 so y = 5.

then you put the value of y that we just found back into one of the equations given to figure out the numerical value of x, so, x -2(5) = -7

solve that and it will be, x = 3.

so the answer is x = 3 and y = 5.

i think this is how you do it, but it has been 2 years since i took a math class involving these problems. i hope i helped you out!

Answer 4

5x - 4y = -5
x - 2y = -7

Multiply the second equation by "-2" entirely:

5x - 4y = -5
-2(x - 2y) = (-2)-7

5x - 4y = -5
-2x + 4y = 14

Now add the equaitons:

(5x - 2x) + (-4y + 4y) = (-5 + 14)
3x + 0 = 9
x = 3

Plug x = 3 in to get y

(3) - 2y = -7
-2y = -10
y = 5

x = 3
y = 5

Answer 5

-2(x-2y=-7) =-2x+4y=14

5x-4y=-5
-2x+4y=14 >add these

3x=9 >divide x=3

5(3)-4y=-5>substitute x for 3

15-4y=-5 -4y=-20>divide, y=5
-15 -15

ANSWER: x=3, y=5

Answer 6

5x+x -4y -2y = -5-7
simplify
6x -6y=-12
x-y=-2
x=y-2

plug into eq2

y-2-2y = -7
simplify
-y=-5
y=5

plug into eq 1 to obtain x
5x-20=-5
x=3

Answer 7

x=3, y=5

I multiplied the bottom row by -5

5x - 4y = -5
-5x+10y=35

Then you add the numbers down.

0 + 6y = 30


y=5

Now we plug "y" into the top equation.

5x - 4y = -5 5x - 20 = -5


5x = 15, x=3


Therefore, x=3, y=5

Answer 8

5x-4y=-5
x-2y=-7

5x-4y=-5
-2(x-2y)=-2(-7)
-2x+4y=14

adding the two together
5x-2x-4y+4y=-5+14
3x=9, x=3
3-2y=-7
-2y=-4, y=2

...it's a real bear to type equations in the dark!

Answer 9

add like terms
5x + x = 6x
-4y + -2y = -6y
-5 + -7= -12

6x -6y = -12

1/6(6x -6y) = (-12)1/6

x-y=2
+y +y

x=y+2
-2 -2

x-2=y

y=x-2

Answer 10

x = y - 2

y = x + 2