Think of it like your drawing it in your head
in my head i would say 8+4=12 carry the 1 so 7+3+1= 11 carry the 1 then 8+5+ 1= 14 so the answer would be 1,412
X^2-2x -3 =0
a =1 b =-2 and c = -3
x = - (-2) +/- sqrt (-2)^2 - 4(1)(-3)
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2(1)
x = + 2 +/- sqrt [(4) - 4(-3)]
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2
x = +2 +/- sqrt [4 + 12]
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2
x = +2 +/- sqrt[16]
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2
x = +2 +/- (4)
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2
x = 2 + 4 or 2 -4
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2 2
x = 6/2 or -2/2
x = 3 or x = -1
740-707.60=32.40
707.60-675.20=32.40
675.20-642.80=32.40
so that means every month you are paying 32.40$ bill. to get how many months you can pay phonebills without depositing any more money devide the 740/32.40=22.83 but you can not pay bill for the 0.83 month so answer will be 22 months