How do I do substitution for this problem

y=4x-9

y=x-3

Over the course of 4 days the price of stock at a corporation fell $28. What was the average change in stock price per day?

How many distinct triangles can be formed for which m∠A = 75°, a = 2, and b = 3?

Difference between the squares of two consecutive numbers is not divisible by 2

What is the equivalent solution to (x+5) - (x-3) (x+5)

Maya runs 100m in 13.4s and Amy can run 100m in 14.1s. If Amy were to finish a 100m race at the same time as Maya, how much of a head start, in meters, will Amy need? What information is known and unknown?

McKenna rode 3.8 miles on her bike last Saturday. Convert this number to a fraction in simplest form.

Jake carries a green a yellow and a black guitar pic in his pocket he randomly chooses a guitar pic from his pocket before every concert what is the probability he will select the same color pic for two concerts in a row

Keith has p pennies, n nickels, and d dimes in his pocket. the total number of coins is 9. the expression 0.01p+0.05n+0.10d0.01p+0.05n+0.10d represents the value of the coins, which is equal to $0.53. he has two fewer nickels than dimes.

Is 2468 a rational or irrational number

A 15 foot ladder is leaning against a wall. if the foot of the ladder is sliding away from the wall at a rate of 10 ft/sec, at what speed is the top of the ladder falling when the foot of the ladder is 9 feet away from the base of the wall?