Suriin ang IDNStudy.com para sa mabilis at kaugnay na mga sagot. Sumali sa aming platform ng tanong at sagot upang makatanggap ng mabilis at eksaktong tugon mula sa mga propesyonal sa iba't ibang larangan.

Eric is twice as old as his brother Lucas. If 4 is subtracted from Eric's age and 4 is added to Lucas' age, their ages will be equal. What are the boys' ages now?

Sagot :

Lets represent:
x=Eric's age
y=Lucas's Age

The first equation:
x=2y

The second equation:
x-4=y+4
Substitute
2y-4=y+4
Subtract y to both sides
y-4=4
Add 4 to both sides
y=8

Therefore: Lucas's age is 8 while Eric's age is 16.

Hope this helps =)

We let Lucas' age be x, this would make Eric's age 2x. 
From the second sentence we would have;
[tex]2x-4=x+4 \\ 2x-4-x=x+4-x \\ x-4=4 \\ x-4+4=4+4 \\ x=8[/tex]

Therefore Lucas' age is 8 and Eric's is 2*8 or 16.