Answer:
9
Step-by-step explanation:
Let's say Mark is M and his brother is B.
M+5=B
M+B=23
Now we can solve using subsitution.
M+M+5=23
(Subtract 5 from both sides)
2M=18
M=9
Hope this helped!
Answer:
49
Step-by-step explanation:
f(5)=8×5+9=40+9=49
Answer:
19 and 26
Step-by-step explanation:
The other 2 cant work because that would make the total Degrees inside the triangle more than 180 (this is impossible)
