Answer:

Step-by-step explanation:
2)
a) elimination method
b) substitution method
c) substitution method
For the first part we can elimate the y variable by subtracting the equations. We can then find the value of x.
For the second part we can substitute y as 2x+5 in the second equation and solve for x.
For the third part we can substitute y as 4x+3 in the first equation and solve for x.
3)

4+8 is 12 so yes it is correct!!!
1)7; divide by 7 2)-3; divide by 2 3)8; divide by -4 4)54; multiply by 6 5)80; multiply by -10 6)-6; divide by -9 7)-5; divide by -12 8)-40; multiply by 20 9)-90; multiply by 10 10)20 11)615; plug in 205 for R and 3 in T. multiply by 3
Answer: 20
Step-by-step explanation: