How do you solve the system of equations #2r - 9s = - 59# and #9r + 2s = 32#?

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Answer 1 · 2018-01-30T11:27:01

Solution: #r=2 , s=7 #

#2r-9s= -59 ; (1) and 9r + 2s = 32 ; (2)# .Multiplying

equation (1) by #9# and multiplying equation (2) by #2# we

get, #18r-81s= -531 ; (3) and 18r + 4s = 64 ; (4)#.

Subtracting equation (3) from equation (4) we get,

#85s = 595 or s = 595/85 = 7 # . Plugging in #s=7# in

equation (2) we get # 9r+2 *7=32 or 9r =32-14 # or

#9r=18 :. r= 18/9=2 :. s=7 , r=2 #

Solution: #r=2 , s=7 # [Ans]