-y^2+17y-42=0

Solution for -y^2+17y-42=0 equation:

Simplifying
-1y2 + 17y + -42 = 0

Reorder the terms:
-42 + 17y + -1y2 = 0

Solving
-42 + 17y + -1y2 = 0

Solving for variable 'y'.

Factor a trinomial.
(-14 + y)(3 + -1y) = 0

Subproblem 1
Set the factor '(-14 + y)' equal to zero and attempt to solve:

Simplifying
-14 + y = 0

Solving
-14 + y = 0

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

Add '14' to each side of the equation.
-14 + 14 + y = 0 + 14

Combine like terms: -14 + 14 = 0
0 + y = 0 + 14
y = 0 + 14

Combine like terms: 0 + 14 = 14
y = 14

Simplifying
y = 14
Subproblem 2
Set the factor '(3 + -1y)' equal to zero and attempt to solve:

Simplifying
3 + -1y = 0

Solving
3 + -1y = 0

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

Add '-3' to each side of the equation.
3 + -3 + -1y = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -1y = 0 + -3
-1y = 0 + -3

Combine like terms: 0 + -3 = -3
-1y = -3

Divide each side by '-1'.
y = 3

Simplifying
y = 3
Solution
y = {14, 3}