-4r-11=4r+21
Move 4r to the other side
Sign changes from +4r to -4r
-4r-4r-11=4r-4r+21
-4r-4r-11=21
-8r-11=21
Move -11 to the other side
Sign changes from -11 to +11
-8r-11+11=21+11
-8r=21+11
-8r=32
Divide both sides by -8
-8r/-8=32/-8
Answer: r=-4
Well, if you take x to be 25 seconds, there are 2.4x in 1min. So, that multiplied by 60, would be 144x. Therefore, 1/4 multiplied by 144x should be the answer.
32 divided by 4/5=32*5/4/
simplify:8*5=40
there are 40 4/5 foot pieces in 32 feet
1/2 x 3/4
1 x 3 / 2 x 4
= 3/8