RT=RS+ST=17+8.5=25.5 units
Answer: VI)

VII)

Step-by-step explanation:
VI)



VII)



Can't type fast enough, LaTex is hard :(
Answer: 18
Step-by-step explanation: You would substitute x for 3 in the expression. This would equal 21-3, or 18 when simplified
The common solution by graphing will be.. x=1