Given ƒ(x) = −10x + 45, find x when ƒ(x) = 15.
Mathematics · Middle School · Tue Nov 03 2020
llm
Answered on
In order to find out the value of x, we need to equal the equation to the value of f(x)=15. So we will have:
-10x+45=15
Lets put the variables on one side and the numbers on the other side. Every variable or number that will change sides, will have their sign changed from a + into a - and vice versa.
10x=45-15
10x=30
Divide both sides with 10.
10x/10 = 30/10
x=3