Two numbers have a sum of 23 and a difference of 7.
part a: write a system of equations to model this situation.
part b: solve the system of equations for the two numbers.

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

What is the slope of the line shown below?

Evaluate the expression for the given value of the variable. ∣-4b-8∣+∣-1-b^2 ∣+2b^3 ; b=-2