25r^2+5r-42=

Solution for 25r^2+5r-42= equation:

Simplifying
25r2 + 5r + -42 = 0

Reorder the terms:
-42 + 5r + 25r2 = 0

Solving
-42 + 5r + 25r2 = 0

Solving for variable 'r'.

Factor a trinomial.
(-7 + -5r)(6 + -5r) = 0

Subproblem 1
Set the factor '(-7 + -5r)' equal to zero and attempt to solve:

Simplifying
-7 + -5r = 0

Solving
-7 + -5r = 0

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

Add '7' to each side of the equation.
-7 + 7 + -5r = 0 + 7

Combine like terms: -7 + 7 = 0
0 + -5r = 0 + 7
-5r = 0 + 7

Combine like terms: 0 + 7 = 7
-5r = 7

Divide each side by '-5'.
r = -1.4

Simplifying
r = -1.4
Subproblem 2
Set the factor '(6 + -5r)' equal to zero and attempt to solve:

Simplifying
6 + -5r = 0

Solving
6 + -5r = 0

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

Add '-6' to each side of the equation.
6 + -6 + -5r = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -5r = 0 + -6
-5r = 0 + -6

Combine like terms: 0 + -6 = -6
-5r = -6

Divide each side by '-5'.
r = 1.2

Simplifying
r = 1.2
Solution
r = {-1.4, 1.2}