SOLUTION: Solve the simultaneous equations; 3a+3b=7.5 5a-2b=9

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Question 722114: Solve the simultaneous equations;
3a+3b=7.5
5a-2b=9

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
3.00 a + 3.00 b = 7.50 .............1
Total value
5.00 a -2.00 b = 9.00 .............2
Eliminate y
multiply (1)by 2.00
Multiply (2) by 3.00
6.00 a 6.00 b = 15.00
15.00 a -6.00 b = 27.00
Add the two equations
21.00 a = 42.00
/ 21.00
a = 2.00
plug value of a in (1)
3.00 a + 3.00 b = 7.50
6.00 + 3.00 b = 7.50
3.00 b = 7.50 -6
3.00 b = 1.50
b = 0.50