Question

The sum of three numbers is 51 . the second number is 2 times the third. the third number is 9 more than the first. what are the numbers?

Answer 1

X+y+z=51

y=2z
z=9+x

subsitute those

x+2z+9+x=51
x+2(9+x)+9+x=51
x+18+2x+9+x=51
4x+27=51
minus 27 both sides
4x=24
divide by 4
x=6

sub back

z=9+x
z=9+6
z=15

y=2z
y=2(15)
y=30

the numbers are
6,30,15

Answer 2

Sum of three numbers = 51
1. Write Out Equation Using Giving Info:
x + 2x + x + 9 = 51
2. Combine Like Terms:
4x + 9 = 51
3. Evaluate for X:
4x = 42
4. Divide both sides by 4:
x = 10.5

First: 10.5, Second: 39, Third: 19.5