3x+y=15

5x-4y=8

resolucion de sistema por el metodo de sustitucion

x=4

y=3

Step-by-step explanation:

we have the following equations

3x+y=15 equation 1

5x-4y=8 equation 2

using equation 1 we have:

y=15-3x equation 3

using equation 3 in equation 2 we have:

5x-4 (15-3x) = 8

5x-4*15+4*3x = 8

5x-60+12x = 8

17x=68

x=68/17

so we have x=4

finally in equation 3:

y = 15-3 (4)

y = 15-12

y = 3