X^2 - y^2 = a
2xy = b
x^2 + y^2 = c
A polynomial identity is an equation that is always true.`1
You can relate x^2 + y^2 with x^2 - y^2 and 2xy in this ways.
1) Step 1:
[x^2 + y^2]^2 = x^4 + 2(xy)^2 + y^4 = c^2
2) Step 2:
[x^2 - y^2] = x^4 - 2(xy)^2 + y^2 = a^2
(2xy)^2 = 4(xy)^2 = b^2
x^4 - 2(xy)^2 + y^2 + (2xy)^2 = x^4 + 2(xy)^2 + y^2
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↓ ↓ ↓
a^2 b^2 = c^2
Answer: the identity is
c^2 = a^2 + b^2 equivalent to
(x^2 + y^2)^2 = (x^2 - y^2)^2 + (2xy)^2
You are looking for how many miles the car went in 1 hour. You know it went 500 miles in 6.7 hours. To find how many it went in 1 hour simply Divide 500 miles by 6.7 hours.
500 miles/6.7 hours = ____ miles in 1 hour
I think it could be 73. Because if you check what it the question says 73 fits them.
A they should work on managing income what they spend and what they earn so they could spend less and make more make sense <span />
