I think that the answe my be b
Answer:
please write this question in English then I give answer
From my research, the original system of equations contain the following equations:
<span>2x − y = −4
3x + 5y = 59
where obtained solution is x = 3
Among the choices, it is easier to substitute </span><span>3x + 5y = 59 with one of the choices to see if they yield the same solution set. From trial-and-error, the equation that can replace the original equation is " 13x = 39 ". Among the choices, it is the 4th choice.</span>
13 divided by 1997 is 0.0065097646
Answer:
b/(b+a)
Step-by-step explanation:
(1/a)-(1/b) :[ (b²-a²)/ab²]
first solve :
common denominator ab
(1/a)-(1/b) = (b-a)/ab
[b-a/ab] : [(b²-a²)/ab²]
when divide fraction ( division sign turn to (×) and flip the second fraction(reciprocal):
[b-a/ab] × [ab²/ (b²-a²)]
then simplify : ab²/ab = b
(b-a)×(b/b²-a²)
factorize : b²-a² = (b-a)(b+a)
(b-a)×(b/(b-a)(b+a)) simplify : (b-a)/b-a = 1
[(b-a)(b)]/[(b-a)(b+a)
b/b+a