Question

Write the linear function f with the given value
f(5)=-1,f(0)=-5​

Answer 1

`y=(4)/(5) x-5.`

Explanation:

1) the common form of linear function in slope=interseption form is: y=s*x+i, where 's' and 'i' are slope and interception, unknown numbers;

2) if f(0)=-5, that means i=-5 and the equation is y=s*x-5, where s - unknown number;

3) f(5)=-1 and if to substitute x=5; y= -1 into y=x*s-5, then it is possible to calculate the value of 's': -1=5s-5; ⇒ s=4/5;

4) finally, the required linear function is:

`y=(4)/(5) x-5`.

P.S. note, the suggested way is not the shortest one.