Use the substitution method to solve the system of equations 8x5y=9 y=x+7

Which of the following exponentially equations is equivalent to the logarithmic equation below?

Which situation is an example of an observational study?

Luigi is the first person to finish a 5k race and is standing 13 feet beyond the finish line. another runner, mario, is still running the race and has approximately 24 feet before he reaches the finish line. what is the distance between mario and luigi? explain through words, numbers or pictures how you found the answer.