How would i solve 7r=-7/2? i know the answer is -1/2 i just don't understand how to get -1/2 as my answer.

With these: 18/36 = 1/? missing number change 1 5/8 to improper fraction. change 19/5 to a mixed number.

What is r i 4.5+10r=-6.5 with work pls

Aright triangle has an area of 21 m2. the dimensions of the triangle are increased by a scale factor of 4. what is the area of the new triangle