Question

Alguém me ajuda nos dois exercicios ?

Answer 1

12) (p+2).x² + (2p+5).x + 2 = 0
x1 = -1

(p+2).(-1)² + (2p+5).(-1) + 2 = 0
(p+2).1 -2p - 5 + 2 = 0
p+2 - 2p - 5 + 2 = 0
-p +4 - 5 = 0
-p = 5 - 4
-p = 1 .(-1)
p = 1

13) (3k/2).x² + (k-3).x - 5/2 = 0
x1 = -1/2
(3k/2).(-1/2)² + (k-3).(-1/2) - 5/2 = 0
(3k/2).(1/4) - (k-3)/2 - 5/2 = 0 
3k/8 - 2k/3 - 5/2 = 0
mmc (8,3,2) = 24
(24:8.3k) - (24:3.2k) - (24:2.5) = 0
3.3k - 8.2k - 12.5 = 0
9k - 16k - 60 = 0
7k = 60
k = 60/7