4u^2-15u-784=0

Solution for 4u^2-15u-784=0 equation:

Simplifying
4u2 + -15u + -784 = 0

Reorder the terms:
-784 + -15u + 4u2 = 0

Solving
-784 + -15u + 4u2 = 0

Solving for variable 'u'.

Factor a trinomial.
(-49 + -4u)(16 + -1u) = 0

Subproblem 1
Set the factor '(-49 + -4u)' equal to zero and attempt to solve:

Simplifying
-49 + -4u = 0

Solving
-49 + -4u = 0

Move all terms containing u to the left, all other terms to the right.

Add '49' to each side of the equation.
-49 + 49 + -4u = 0 + 49

Combine like terms: -49 + 49 = 0
0 + -4u = 0 + 49
-4u = 0 + 49

Combine like terms: 0 + 49 = 49
-4u = 49

Divide each side by '-4'.
u = -12.25

Simplifying
u = -12.25
Subproblem 2
Set the factor '(16 + -1u)' equal to zero and attempt to solve:

Simplifying
16 + -1u = 0

Solving
16 + -1u = 0

Move all terms containing u to the left, all other terms to the right.

Add '-16' to each side of the equation.
16 + -16 + -1u = 0 + -16

Combine like terms: 16 + -16 = 0
0 + -1u = 0 + -16
-1u = 0 + -16

Combine like terms: 0 + -16 = -16
-1u = -16

Divide each side by '-1'.
u = 16

Simplifying
u = 16
Solution
u = {-12.25, 16}