2x^2 - 7x - 4
Multiply 2 and 4
x^2 - 7x - 8
(x - 8) (x + 1)
Divide by 2 for both numbers to bring the 2 back that was multiplied
(x - 4) (2x + 1)
(x - 4)
x - 4 = 0
+4 on both sides
x = 4
(2x + 1)
2x + 1 = 0
-1 on both sides
2x = -1
/2 on both sides
x = -1/2
Answer:
x = 4
x = -1/2