Question

Solve, using linear combination.

p – q = 8
2p – q = 19



Which ordered pair, (p, q), is the solution to the system of equations?



A (4, –4)

B (10, 1)

C (–4, 4)

D (11, 3)

Answer 1

p - q = 8.....multiply by -1
2p - q = 19
----------------
-p + q = -8 (result of multiplying by -1)
2p - q = 19
---------------add
p = 11

now we sub 11 in for p in either of the original equations to find q
p - q = 8
11 - q = 8
11 - 8 = q
3 = q

so ur solution is (11,3)