Question

Look at this linear equation.
3x + 5y = 30

Which of the following equations can be used to solve for y in the linear equation above?
y = - x + 30
y = 3x + 6
y = - x + 6
y = x + 30

Answer 1

3x + 5y = 30 (solve for y) -- subtract 3x from both sides
5y = -3x + 30 -- divide both sides by 5
y = -3/5x + 30/5 -- reduce when you can
y = -3/5x + 6

Answer 2

y=3x+6
find value os 3x fro this and put it in orignal linear eq..the value os 3x will be
3x=y-6
put it in linear eq.
so
y-6+5y=30
=>6y=30+6
=>6y=36
=>y=6 answer