3(4x+6)=-4

What property did you use to solve this problem?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?

Atemperature of 1.64◦f corresponds to answer in units of ◦c.

Find the ratios of the corresponding sides