Respuesta :

loneguy

[tex]y = 10x +2~~....(i) \\\\-5x +4y = -27~~....(ii)\\\\\text{Substitute y =10x+2 in equation (ii):}\\\\\\-5x +4(10x+2) = -27 \\\\\implies -5x + 40x + 8 +27 =0\\\\\implies 35x +35=0\\\\\implies 35(x +1) =0\\\\\implies x +1 = 0 \implies x = -1\\\\\text{Substitute} ~x =-1 ~ \text{in equation (i):}\\\\y = 10(-1) +2 = -10+2 = -8 \\\\\\\text{Hence}~ (x,y) = (-1,-8)[/tex]

sqdancefan

Answer:

  (x, y) = (19/35, 52/7)

Step-by-step explanation:

When you have an expression for one of the variables, the "substitution" method of solution is a reasonable choice. Here, we have an expression for y that can be substituted into the second equation.

  -5x +4(10x +2) = 27

  35x +8 = 27 . . . . . . . simplify

  35x = 19 . . . . . . . subtract 8

  x = 19/35 . . . . divide by the coefficient of x

  y = 10(19/35) +2 = 52/7

The solution is (x, y) = (19/35, 52/7).

Otras preguntas