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