Answer:
RM = 12 cm
Step-by-step explanation:

Assuming 20 is the hypotenuse cus there is no picture:




If It's not the hypotenuse:




But I find it unlikely that 20 wasn't the hypotenuse so ignore that unless it applies.
Hope this helped. :0)
Hello :
<span>3-x/2=6
</span><span>-x/2=6 -3
</span>-x/2=3
- x = 6
x = - 6
5:4 Should be correct! I took the test Btw Hope this helps!! :D