SOLUTION: In 3 years,Carlo will be 3 times as old as his sister Daisy. A year ago, Carlo was 7 times old as Daisy. How old are they now i need a solution about "problems involving systems

Algebra.Com
Question 806958: In 3 years,Carlo will be 3 times as old as his sister Daisy.
A year ago, Carlo was 7 times old as Daisy. How old are they now
i need a solution about "problems involving systems of linear equations".. please help me

Answer by josgarithmetic(39620)   (Show Source): You can put this solution on YOUR website!
c is carlo's age
d is daisy's age

c+3=3(d+3).
c-1=7(d-1), but the worded description might be ambiguous.

Organizing each equation into the same form,
c+3=3d+9
c-3d=9-3
c-3d=6
'
c-1=7d-7
c-7d=-7+1
c-7d=-7
'
The system of equations is



Use any method you know to solve the system. You could solve each equation for c and equate those expressions to solve for d; or you could subtract one equation from the other and solve for d. You could then solve for c knowing your value for d.

RELATED QUESTIONS

In 3 years,alex will be 3 times as old as his sister Precy.A year ago,Alex was 7 times as (answered by alka001)
In 3 years, alex will be 3 times as old as his sister precy. a year ago, alex was 7 times (answered by Fombitz)
in 3 years David will be 3 times as old as his sister martha. A year ago David was 7... (answered by josgarithmetic)
In 3 years, david will be 3 times as old as his sister Marina, a year ago, David was 7... (answered by josmiceli)
in 3 years angelo will be 3x as old as his sister Precy, a year ago angelo was 7 times as (answered by Theo,josgarithmetic,greenestamps)
PLEASE help me for this :( -- In 3 years, Alex will be 3 times as old as his sister... (answered by scott8148)
in 3 years, alex will be 3 times as old as prency. a year ago, alex was 7 times as old as (answered by mananth)
In 3 years, Alex will be 3 times as old as his sister Precy. A year ago, Alex was 7 times (answered by bucky)
in 3 years,alex will be 3 times as old as his sister precy,a year ago alex was 7 times as (answered by Theo)