Solve by using a system of two equations in twovariables. Show and explain each

Question

Solve by using a system of two equations in twovariables. Show and explain each step. Five years ago, Jerry was 2/3 as old as Jeff. Ten yearsfrom now, he will be 5/6 as old as Jeff will be. How old iseach now?    P.S. The teacher said the answers should be Jerry is 15years old and Jeff is 20 years old. I had y-5 =2/3(f-5) and y + 10 = 5/6(y+10) but I can't seem to getthe right answer from those equations. Are the equationswrong and how do you solve them???? Solve by using a system of two equations in twovariables. Show and explain each step. Five years ago, Jerry was 2/3 as old as Jeff. Ten yearsfrom now, he will be 5/6 as old as Jeff will be. How old iseach now?    P.S. The teacher said the answers should be Jerry is 15years old and Jeff is 20 years old. I had y-5 =2/3(f-5) and y + 10 = 5/6(y+10) but I can't seem to getthe right answer from those equations. Are the equationswrong and how do you solve them????

Explanation / Answer

Here's how I worked it: y-5=2/3(f-5) multiplying both sides by 3, to get rid of the fraction Iget: 3y-15=2(f-5) Simplify 3y-15=2f-10 3y=2f-5 y=(2/3)f-(5/3) That's all I can do with that equation. Using the secondequation I have y+10=5/6(f+10) multiply thru by 6 to get rid of the fraction 6y+60=5(f+10) distribute the 5 6y+60=5f+50 6y=5f-10 Now I'm going to plug in y=(2/3)f+(5/3) into the aboveequation. (I got that from Eq. 1) 6((2/3)f+(5/3))=5f-10 distributing the 6, I get  12/3f+30/3=5f-10 or 4f+10 = 5f-10 so: 4f =5f-20 and -f = -20 or f=20 Plugging f=20 into the first equation y=(2/3)f+(5/3) y=(2/3)(20) + (5/3) y=15 Hope that helps! You were on the right course. But youmissed an 'f' in Eq. 2

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.