We have the following expression: 0 = -4x ^ 2 + 7 x - 8 The first thing we must do in this case is to rewrite the expression. For this, we use the resolver, where: a = -4 b = 7 c = -8 Getting: 0 = (1/8) * (7 +/- i * root (79)) Answer: The equation has NO real solutions.