Question

Solve by method of elimination by equating coefficients:

10y = 7x - 4

12 x+ 18y = 1

Answer 1

7x-10y-4=0_________(1)
12x+18y-1=0_______(2)
________________________
for equating co.eff.
(1)×18;
126x-180y-72=0________(3)
(2)×10;
120x+180y-10=0________(4)
_____________________________
(3)+(4) gives;
246x=82
x=82/246=1/3.
put x=1/3 in (1)
then
7×(1/3)-10y-4=0
10y =-5/3
y=-5/(3×10)
=-5/30
=-1/6.