To find the solutions for these quadratic equations, we can use the quadratic formula:

For the first equation, 5x^2 + 8x - 4 = 0:
a = 5, b = 8, c = -4

x = (-b ± √(b^2 - 4ac)) / 2a
x = (-8 ± √(8^2 - 45(-4))) / 2*5
x = (-8 ± √(64 + 80)) / 10
x = (-8 ± √144) / 10
x = (-8 ± 12) / 10

Therefore, the solutions for the first equation are:
x = (-8 + 12) / 10 = 4 / 10 = 0.4
x = (-8 - 12) / 10 = -20 / 10 = -2

For the second equation, 2x^2 - 2x + 9 = 0:
a = 2, b = -2, c = 9

x = (-b ± √(b^2 - 4ac)) / 2a
x = (2 ± √((-2)^2 - 429)) / 2*2
x = (2 ± √(4 - 72)) / 4
x = (2 ± √(-68)) / 4

As the square root of -68 is an imaginary number, the solutions for the second equation are complex numbers and are given by:
x = (2 ± √68i) / 4