For the following pairs of equations, how to write s in terms of a only? : 1) 3s-ah=a^2 and as+2h=3a 2) as=s+h and ah=a+h.

1 Answer
Jan 22, 2018

(1) s=5a26+a2 and (2) s=a(a1)2

Explanation:

As we have three variables a,s andh, we eliminate h to get s in terms of a only.

(1) As 3sah=a2, ah=3sa2 and h=3saa

and as as+2h=3a, 2h=3aas and h=32aas2

hence 3saa=32aas2

and multiplying each term by 2a, we get

6s2a2=3a2a2s

or s(6+a2)=5a2 or s=5a26+a2

(2)As as=s+h, we have h=ass=s(a1)

and as ah=a+h, we have ahh=a or (a1)h=a or h=aa1

Hence aa1=s(a1)

or s=a(a1)2