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:
You are correct. Remember: rise over run.
m = 
Answer:42
Step-by-step explanation:
V= 18 + 6(4)
V= 18 + 24
V= 42
The correct answer is 23/6. Hope this helps.
Answer:
x = 51
Step-by-step explanation:
(x-3) /4 = 12
Multiply each side by 4
(x-3) /4 *4 = 12*4
x-3 = 48
Add 3 to each side
x-3+3 = 48+3
x = 51