Question

If the first equation is multiplied by 3 and then the equations are added, the result is _____. 3x + y = 3 x - 3y = -2 10 x = 7 10 x = 11 8 x = 7.

Answer 1

if the first equation 3x - 3y = -2 is multiplication by 3

therefore, 3x - 3y = -2

multiplied by 3

:9x - 9y = -6

then the equations are added,

9x - 9y = -2 + 10x + 710x + 118x + 7

9x + 10x + 710x + 118x + 9y + 7

947x + 9y = 7