Answer:
(r-7) ÷ (6+?)
Step-by-step explanation:
I don't know what the last number is
Answer:
the answer is 44 students.
Step-by-step explanation:
1 and half hour
= 60 minutes+ 30 minutes
= 90 minutes
Now,
Uzanne need 15 minutes to do 10 problems
Uzanne need 1 minute to complete 10/15 problems
Uzanne need 90 minutes to do
= (10/15)*90
=(2/3)*90
=2*30
=60 problems
Answer:

Step-by-step explanation:
we would like to factor the following:

let a²+b²=x
thus substitute:

rewrite the middle term as 4x-22x:

factor out x:

factor out -22:

group:

substitute back:

and we are done!