The sum of Kris and Victor's ages is 27 years. In three years, Victor will be three times as old as Kris. What are their present ages?
Find the solution using only one variable.
The sum of Kris and Victor's ages is 27 years. In three years, Victor will be three times as old as Kris. What are their present ages?
Find the solution using only one variable.
Let $\displaystyle K$ be Kris' age and $\displaystyle V$ be Victor's age.
The statement "The sum of Kris and Victor's ages is 27 years" becomes what equation?
The statement "In three years, Victor will be three times as old as Kris" becomes what equation?
Post what you think, and we will guide you from there,
Well, you are given two unknowns and two statements which are essentially equations, so the easiest way is to use two variables, and the two statements to get a 2X2 linear system.
Are you not studying systems of equations?
"The sum of Kris and Victor's ages is 27 years"
y+(27-y)=27
"In three years, Victor will be three times as old as Kris" I got the 1st part i think, but i don't know what goes on the right side of the equation.
27-y+3 (would be victor's age in three years) and y+3 (would be kris's age) but i don't know how to put them together.
we are learning how to solve equations with one variable. So 27-y would be the second variable. We have not been using two variables in class, so I don't know if my teacher would be ok with me using more than one.
Okay, this seems an odd way to go about it, since if we write:
$\displaystyle K+V=27$
We find:
$\displaystyle K=27-V$
Now, for the second statement, I would write:
$\displaystyle V+3=3(K+3)$
Which gives us:
$\displaystyle V+3=3(27-V+3)=3(30-V)$
And now I would solve for $\displaystyle V$.