[bratzdoll3]

what's the x coordinate of the solution of the following system od linear equations?
-3x-5y=-23
2x-4y=-14

is the answer

a. 4
b. 0
c. -4
d. -1
e. 1

how do you do this?

[Capuchin]

for simultaneous equations, you need to multiply up so you can get rid of a variable.

In this case you want X, so we need to get rid of y

If you multiply all terms in your top equation by 4 and all terms in your bottom equation by 5, you will have 2 equations both with -20y in them.

You can then subtract the two equations, ending up with 0y and an amount of x, it's then simple algebra to solve for x.

Let me know how you get on!

[CaptainForest]

If I have done my math correct…..

-3x-5y=-23
2x-4y=-14

-5y=-23 + 3x
-4y =-14 – 2x

y = 4.6 - 0.6x
y =3.5 + 0.5x

3.5 + 0.5x = 4.6 - 0.6x
0.6x + 0.5x = 4.6 – 3.5
1.1x = 1.1
x = 1

[Capuchin]

Ewww dividing.

Multiplying up is your friend.

[CaptainForest]

-5y=-23 + 3x
x4
= -20y = -92 + 12x


-4y =-14 – 2x
X 5
= -20y = -70 – 10x


-92 + 12x = -70 – 10x
12 x + 10 x = -70 + 92
22x = 22
x = 1

I still get x=1

[Capuchin]

Well yes... I'm not saying you're wrong :p

[CaptainForest]

Lol