SOLUTION: Please help to solve 1/5x - 5/2y = -48 0.4x + 0.05y = 5 thank you!

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Question 65589This question is from textbook An Incremental Development
: Please help to solve
1/5x - 5/2y = -48
0.4x + 0.05y = 5
thank you! This question is from textbook An Incremental Development

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
E1) 1/5x - 5/2y = -48
E2) 0.4x + 0.05y = 5
What makes this system harder to solve is the fractions and decimals, so let's eliminate them by multiplying E1 by the LCD, 10, and E2 by 100 to move the decimals two spots to the right.
:
E1) 10%281%2F5%29x%2B10%28-5%2F2%29y=10%28-48%29 ---> 2x-25y=-480
E2) 100(.4x)+100(0.05y)=100(5) --> 40x+5y=500
Multiply E1 by -20 and add it to E2 to eliminate the x's:
E1) -20(2x)-20(-25y)=-20(-480) --> -4x+50y=960
:
E1) -40x+500y=9600
E2) 40x+5y=500
_______________
0x+505y=10100
505y=10100
505y/505=10100/505
highlight%28y=20%29
Substitute 20 in for y in either equation and solve for x.
(1/5)x-(5/2)(20)=-48
(1/5)x-50=-48
(1/5)x-50+50=-48+50
(1/5)x=2
5(1/5)x=5(2)
highlight%28x=10%29
Therefore the coordinate form of the solution is: (x,y)=(10,20)
Happy Calculating!!!