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Mathematics

1 answer:

podryga [215]3 years ago

7 0

Answer:

x=8.499

y=0.167

Step-by-step explanation:

the equation says:x^2-9y^2=72....(1)

x+3y=9.......(2)

divide (2) from (1),it becomes:

x-3y=8

making x subject of formula,

x=8+3y....(3)

submitting (3) into (1),it becomes

(8+3y)^2-9y^2=72

64+48y=72

48y=72-64=8

y=8/48=0.167......(4)

submitting (4) into (2),it becomes

x+3(0.167)=9

x+0.501=9

x=9-0.501

x=8.499

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