Question #a9fdf
1 Answer
Nov 6, 2016
Explanation:
Rearrange x + 5y in terms of x or y and substitute into xy = 6.
x+y=5rArry=5-x substitute this into xy = 6
rArrx(5-x)=6 distribute and equate to zero.
rArr5x-x^2=6rArrx^2-5x+6=0 Factorising the quadratic gives.
(x-2)(x-3)=0rArrx=2,x=3
x=2toy=5-2=3to(2,3)" is a solution"
x=3toy=5-3=2to(3,2)" is also a solution" This can be checked fairly ' easily' as follows.
x=2,y=3rArrx+y=2+3=5" and " xy=2xx3=6
x=3,y=2rArrx+y=3+2=5" and " xy=3xx2=6