Si estás tratando a encontrar M este es
13-8m=21
8m=8
M=1
The best method for solving the system of linear equation is by the use of algebraic methods.
The system of linear equations can be solved by using the method of simultaneous equations. Here we are given two equations and two unknown variables. We can solve the same by eliminating one of the variables and then either adding or subtracting, find the value of the other variable. Once we know the value of one variable, then we can substitute its value in any one given equation and find the second variable. This method is said to be accurate and does not involve any error.
Hence answer is : USE ALGEBRAIC METHODS
Answer:
dy/dx at x=6 is 0.334
Step-by-step explanation:
The center difference method requires that the values of the function are given in equal intervals which is the case, and allows one to find the value for x = 6 using those of the function for x = 5.5 and for x = 6.5 as follows:

1 lemon costs 20p and 1 orange costs 45p so an orange costs 25p more