The Smiths are moving across the country. Mr. Smith leaves 4 hours before Mrs. Smith. If he averages 60mph and she averages 80mph, how many hours will it take Mrs. Smith to catch up to Mr. Smith?

60 miles per hour x 4 hours = 240 miles

Mr smith was 240 miles ahead of Mrs/ smith

The difference in speeds was 80 - 60 = 20 miles per hour

240 miles / 20 miles per hour = 12 hours.

It takes 12 hours to catch up.

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions