SOLUTION: solve the following pair of simultaneous equations. 3/5x - 4y = -1 0.8x - 3.5y = 1/2

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Question 1169747: solve the following pair of simultaneous equations.
3/5x - 4y = -1
0.8x - 3.5y = 1/2

Found 2 solutions by ankor@dixie-net.com, MathTherapy:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
solve the following pair of simultaneous equations.
3/5x - 4y = -1
0.8x - 3.5y = 1/2
Get rid of these annoying numbers, multiply both eq by 10
6x - 40y = -10
8x - 35y = 5
multiply 1st eq by 8, the 2nd eq by 6
48x - 320y = -80
48x - 210y = 20
------------------subtraction eliminates x, find y
0 - 110y = -100
multiply by -1
110y = 100
y = 100/110
y = 10%2F11
find x
8x - 35(10%2F11 = 5
8x - 350%2F11 = 5
8x = 55%2F11 + 350%2F11
8x = 405%2F11
x = 405%2F88
:
:
Check using the 2nd original equation, using a calc
.8(405%2F88) - 3.5(10%2F11) = .5

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

solve the following pair of simultaneous equations.
3/5x - 4y = -1
0.8x - 3.5y = 1/2
The other person's answers are WRONG!!

When solving systems, always try to work with the smallest numbers possible
Now, to get rid of the decimals and fractions, we multiply eqs (i) & (ii) by 10 to get:
6x - 40y = - 10 --- eq (iii)
8x - 35y = 5 ------ eq (iv)
You then multiply eq (iii) by 4 and eq (iv) by 3 to get:
24x - 160y = - 40 ---- eq (v)
24x - 105y = 15 ------ eq (vi)
55y = 55 ------ Subtracting eq (v) from eq (vi)
highlight_green%28matrix%281%2C5%2C+y%2C+%22=%22%2C+55%2F55%2C+%22=%22%2C+1%29%29
I'll leave "x" for you to find!