If a minus b is equal to 7 then a square + b square equal to 85 find a cube plus minus b cube
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a-b=7
a=7+b
a^2+b^2=85
(7+b)^2+b^2=85
49+b^2+14b +b^2 =85
2b^2+14b =36
b^2+7b = 18
b^2+7b-18=0
b^2-2b+9b -18 =0
b(b-2)+2(b-2)=0
b= 2
a= 9
a^3 +b^3
9^3+2^3
729+8= 737
a=7+b
a^2+b^2=85
(7+b)^2+b^2=85
49+b^2+14b +b^2 =85
2b^2+14b =36
b^2+7b = 18
b^2+7b-18=0
b^2-2b+9b -18 =0
b(b-2)+2(b-2)=0
b= 2
a= 9
a^3 +b^3
9^3+2^3
729+8= 737
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