Una pieza de metal está formada por dos tipos de acero. El acero A contiene un 5 % de níquel, y el acero B que contiene 40%. ¿Que cantidad de cada acero será necesario para obtener 70 toneladas de un nuevo metal que contenga 30 % de níquel?

Se necesitan 20 toneladas de acero A, mientras que se necesitan 50 toneladas de acero B

Step-by-step explanation:

Deje que la cantidad de acero A sea xy la cantidad de acero B sea y.

Queremos obtener 70 toneladas del nuevo metal, por lo tanto;

x + y = 70 •••••••••• (i)

Ahora, nuestro porcentaje final es del 30%

Esto significa que; x (5%) + y (40%) = 70 (30%)

Esto significa; 0.05x + 0.4y = 21 •••••••• (ii)

Entonces resolvemos ambas ecuaciones simultáneamente.

De i, x = 70-y

Sustituir esto en la ecuación ii

0.05 (70 años) + 0.4y = 21

3.5-0.05y + 0.4y = 21

0.35y = 21-3.5

0.35y = 17.5

y = 17.5 / 0.35 = 50 toneladas

Recordar; x = 70-y

x = 70-50 = 20 toneladas.

3. (5x + 1) - (-10x + 6)

simplify the answer choice. combine like terms. remember to distribute the negative to the terms inside the second parenthesis. also remember that two negatives = one positive, and one of each sign = negative.

- (-10x + 6) = + 10x - 6

simplify. combine like terms:

5x + 1 + 10x - 6

5x + 10x + 1 - 6

15x - 5

∴ it is your answer

~

(1, –1), (16, –4), (36, –6)

step-by-step explanation:

given that the function is

this can also be written as

we have to graph this function and check which list of points lie on the graph

see attachment for graph:

we find that the points lying are (1,-1) (16,-4) and (36,-6)

since square root is there we find that x can only be posiitve but y can be since square root both positive and negative.