Question

Do the following points belong to the graph of the function f(x)=13−5x ? (-2,23)

Answer 1

Yes!
You plug in the -2 into x and the 23 into f(x).

f(23)= 13-5(-2)
f(23)= 13+10
f(23)= 23

Answer 2

Yes!

Explanation:

When we have problems like this we just plug them in. We take the -2 and we multiply it by the -5 to get a positive 10. We then add that to the +13 and it equals 23, so it works!