Question

find a point on the line 2x+3y=15 whose abscissa is 3 1/2 times it's ordinate

Answer 1

according to question...
x=7/2y
putting it in the equation of the line...
2x+3y=15
2(7/2y)+3y=15
7y+3y=15
10y=15
y=15/10
y=3/2
now for x,
2x+3y=15
2x=15-3y
x=(15-3y)/2
x=[15-3(3/2)]/2
x=[15-9/2]/2
x=[(30-9)/2]/2
x=[21/2]/2
x=21/4