Proportion/Percent/Rates/ Linear functions

7x-9y=39 35x-45y=195 For a any real number r, which of the following point lies on the graph of both equations?

14cars listed for sale on an auto dealership's website. If one of the cars is selected at random, what is the probability that the car selected will be a hybrid car priced at no more than $25000?

The density of a certain type of wood is 353 kilograms per cubic meter. A sample of this type of wood is in the shape of cube and has a mass of 345 kilograms. To the nearest hundredth of a meter, what is the length of one of this sample?

For the function f, if f(3x)=x-6 for all values of x, what is the value of f(6)=?

The functions f and g are defined f(x)=1/4x-9 and g(x)=3/4x+21. If the function h is defined h(x)=f(x)+g(x), what is the x-coordinate of the x-intercept of the graph of y=h(x) in the xy plane?

If 4a/b=6.7 and a/bn= 26.8 , what is the value of n?

A sample of oak has a density of kilograms per cubic meter. The sample is in the shape of a cube, where each edge has a length of meters. To the nearest whole number, what is the mass, in kilograms, of this sample? A. 588. B. 726.

The international Space Station orbits Earth at an average speed of 4.76 miles per second. What is the space station's average speed in miles per hour?

Jeremy deposited x dollars in his investment account on January 1, 2001. The amount of money in the account doubled each year until Jeremy had 480 dollars in his investment account on January 1, 2005. What is the value of x ?

In the given figure, BC is the diameter of the circle. If the length of BC is equal to 132 and the length of AB is equal to v363, what is the value of BC/BD?

In the given equation, k is a positive constant. The product of the solutions to the equation is 154. What is the value of K?