Question

If 3x+ 5y = 9
and 5x+3y=7 then what is the value of x+y​

Answer 1

Answer:

3|3,5

5|1,5

|1,1

prime factors: 3 and 5

5*(3x+5y=9) + -3*(5x+3y=7)

15x+25y=45 + -15x+(-9y)=(-21)

15x+25y=45

+ -15x+(-9y)=(-21)

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0x -16y=24

0 -16y=24

16y=24

y=24/16

y=1.5

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3x+5y=9. 5x+3y=7

3x+5(1.5)=9. 5x+3(1.5)=7

3x+7.5=9. 5x+4.5=7

3x=9-7.5. 5x=7-4.5

3x=1.5. 5x=2.5

x=1.5/3. x=2.5/5

x= 0.5. x=0.5

_____ _____

3x+5y=9. 5x+3y=7

3(0.5)+5(1.5)=9. 5(0.5)+3(1.5)=7

1.5+7.5=9. 2.5+4.5=7

9=9. 7=7

x+y=?

0.5+1.5=2

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