Let

be the amount of time it takes to perform an arm routine and

be the amount of time it takes to perform an abdominal routine. We see:


Subtracting the second equation from the first gives

. Substituting gives

, so

and

.
Thus, an arm routine takes ten minutes and an abdominal routine takes thirty minutes.
Answer:
all real numbers greater than or equal to 2
which is [2, infinite)
Answer:
y=3x+23 (lmk if you need me to explain)
Step-by-step explanation: