Question

y = x + 4
y = −2x − 2

Explain how you will solve the pair of equations by substitution. Show all the steps and write the solution in (x, y) form.

Answer 1

y=x+4
Putting variable on L.H.S.
y-x=4-----------------(eq.1)

y=-2x-2
Putting variable on the L.H.S.
y+2x=-2---------------(eq.2)

Subtracting Both the equation

y-x=4
(-)y+(-)2x=-(-)2

y-x=4
-y-2x=4
=======
-3x=8
x=-8/3

Putting x in equation 1

y-x=4
y-(-8/3)=4
y+8/3=4
y=4-8/3
y=12-8/3
y=4/3









x=-8/3
and y=4/3