The equations are
\ Equation (1)
Equation (2)
Solve the second equation for p in terms of q.
\Apply addition property of equality; if a = b, then a + c = b + c.
\ (Add 4q to each side)
(Apply Additive inverse property:
)
(Apply Additive identity property:
)
Combine like terms using distributive property: .
Apply division property of equality: if a = b, then.
(Divide each side by 2)
(Cancel common terms)
Substitute in Equation (2).
Distribute terms using distributive property: .
(Multiply:
)
(Apply Additive inverse property:
)
(Apply Additive identity property:
)
q = 0
\Substitute in equation in equation
.
(Apply zero product property:
)
(Apply additive identity property:
)
The solution is .