Please help me ASAP!!

r = -4

Step-by-step explanation:

If M is the midpoint of DE, that would mean that the distance from M to D and M to E would be the same.

This creates the equation 1-8r=13-5r.

Now it's just simple algebra.

You add 8r to both sides, creating 1=13+3r. Then, you subtract 13 from both sides, getting 3r=-12. Dividing both sides by 3 and solving for r, you get r=-4.

Checking our answer, you see that 1-8(-4)=1-(-32)=1+32=33, and 13-5(-4)=13-(-20)=13+20=33.

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this

853.3

step-by-step explanation: