Realmente no entiendo esta pregunta, lo siento mucho, pero espero que lo resuelvas. Lo siento, nuevamente..
Step-by-step explanation:
why ? you did it right there already.
the numerator is the top part of the fraction, the "counting" part (how many units of a certain type or size are there).
the denominator (the bottom part) is defining the type or size of units described by the fraction.
so, we are adding 4 to the numerator of 2/5, making it (2+4)/5 = 6/5
what do we need to add to the denominator (the bottom part) to make the fraction have the value of 1/2 ?
so, what x would make 6/x = 1/2 ?
6 = x/2
x = 6×2 = 12
so, we need to get 12 in the denominator, where we have currently 5.
therefore, we need to add 12-5 = 7 to it.
so that
6/(5+7) = 6/12 = 1/2
21/50, 87/200, 43.7%, 0.44
hope this helps.
27x^2-81x-9x+27 In this case, just in your mind multiply 27 (coefficient of x^2) by the constant value 27(the end value of the quadratic trinomial). Then find factors that give you the value -90 when you add and 729 (27*27) when you multiply.
Factorise the values
27x( x-3)-9(x-3)
Which will give you
(27x-9)(x-3)
