Maria = x
Tom = y
Use substitution
x+y=30
2y=x
2y+y=30
3y=30
y=10
Tom is 10 years old.
x+y=30
x+10=30
x=20
Maria is 20 years old.
Answer:
11
Step-by-step explanation:
Hello,
Given the original number n.

Multiply the number by 9.

Add 99.

Divide this sum by 9.

Subtract the original number, n, from the quotient.

Thank you.
Answer:
y=x+8 and y=3x
Step-by-step explanation:
The Given point is (4,12)
now we can substitute the point in each of the function and check wether it lies on it or not.
A. y=x+8
substitute y=12,x=4
12=4+8=12 which is true
B. y=3x
substitute y=12,x=4
12=3*4=12 which is true
C. y=2x
substitute y=12,x=4
12=2*4=8 which is not true
D. y=x+6
substitute y=12,x=4
12=4+6=10 . which is not true
Therefore option A and B are correct.
Answer is 325 your welcome