My mom wants to burn 240 calories a day by swimming and walking. She burns 8 calories per minute of swimming and 6 calories per minute of walking. If x represents the number of minutes she swims and y represents the number of minutes she walks, then we can represent the combination of swimming and walking that would burn 240 calories as: 8x + 6y = 240 How many minutes will she have to walk if she doesn't do any swimming?
In this problem we have that
the variable x represent the number of minutes she swims
and y represents the number of minutes she walks
8x+2y=240
she doesn't do any swimming-------> x=0
substitute in the given equation
8(0)+2y=240
solve for y
2y=240
y=120 minutes
therefore
the answer is
120 minutes