Question

5×(7×r-5)=225 срочно помогите решить !!!

Answer 1

$5×(7×r-5)=225 \ (7×r-5)=225 div 5 \ 7×r-5=45 \ 7×r = 45 + 5 \ 7×r = 50 \ r = frac{50}{7} \ r = 7 frac{1}{7}$