Question 7 (Essay Worth 5 points) (08.03)Consider the following pair of equations: y = -2x + 8 y = X-1 Explain how you will solve the pair of equations by substitution. Show all the steps and write the solution in (x, y) form​

Aparticular telephone number is used to receive both voice calls and fax messages. suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (a) what is the expected number of calls among the 25 that involve a fax message?