Question

What is the value of s in the equation 3 r equals 10 plus 5 s, when r equals 10?

Answer 1

Well first, you must write the equation out.
3r= 10+5s

Answer 2

so if r equals ten, replace any r variables with 10 and simplify

Answer 3

3 * 10 = 10 + 5s
30 = 10 + 5s

Answer 4

Now we must isolate the s variable to find the answer:
30 = 10 + 5s
30 - 10 = 10 - 10 + 5s
20 = 5s
20/5 = 5s/5
4 = s