Its $800 because to find interest u can use the formula I=PRT p is principal which is 500 times r which is rate-15/100(=15%) times 4
so the interest is 500×15/100×4=300
then u add 300 to 500 because the interest adds more money to the loan
3x + 1 = (x-1)^2
3x + 1 = x^2 - 2x + 1
0 = x^2 -5x
0 = x(x-5)
x = 0,5
Hope this helps!
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The answer is f(x)=x^2+2x-5
A quadratic formula must have at least one square (x^2) and cannot have higher exponents.
The reason 0x^2 doesn't count is because that will always equal zero no matter the value of x, which makes that term a constant.
