SOLUTION: I need to use the system of equations with square roots 3 sqrt ( a ) +5 sqrt ( b ) =31 5 sqrt ( a ) -5 sqrt ( b ) = -15

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Question 869161: I need to use the system of equations with square roots
3 sqrt ( a ) +5 sqrt ( b ) =31
5 sqrt ( a ) -5 sqrt ( b ) = -15
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
3 sqrt ( a ) + 5 sqrt ( b ) = 31
5 sqrt ( a ) - 5 sqrt ( b ) = -15
------------------------------------adding eliminates b
8 sqrt(a) + 0 = 16
sqrt(a) = 16/8
sqrt(a) = 2
square both sides
a = 2^2
a = 4
Find b
3*sqrt(4) + 5*sqrt(b) = 31
3(2) + 5*sqrt(b) = 31
5*sqrt(b) = 31- 6
5*sqrt(b) = 25
sqrt(b) = 25/5
sqrt(b) = 5
b = 5^2
b = 25