answer: 10
step one: replace r with 7 and a with 2
this will bring you to the equation 7+(2+1)^2 ÷3. (if you don’t know “^2” means squared or to the power of 2)
step 2: do what’s in the parenthesis first following PEMDAS which would be (2+1) and 2+1 is 3. now your equation is 7+3^2 ÷3
step 3: do the exponent, 3^2 is 3*3 which equals 9 so the new equation is 7+9 ÷3
step 4: now you have to do division, 9 ÷3 = 3 so our new equation is 7+3
step 5: addition is last and we have to do 7+3 which is 10 so your answer is 10!
hope this was a good explanation!