21r^2+16r-16=0

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Solution for 21r^2+16r-16=0 equation:


Simplifying
21r2 + 16r + -16 = 0

Reorder the terms:
-16 + 16r + 21r2 = 0

Solving
-16 + 16r + 21r2 = 0

Solving for variable 'r'.

Factor a trinomial.
(-4 + -3r)(4 + -7r) = 0

Subproblem 1

Set the factor '(-4 + -3r)' equal to zero and attempt to solve: Simplifying -4 + -3r = 0 Solving -4 + -3r = 0 Move all terms containing r to the left, all other terms to the right. Add '4' to each side of the equation. -4 + 4 + -3r = 0 + 4 Combine like terms: -4 + 4 = 0 0 + -3r = 0 + 4 -3r = 0 + 4 Combine like terms: 0 + 4 = 4 -3r = 4 Divide each side by '-3'. r = -1.333333333 Simplifying r = -1.333333333

Subproblem 2

Set the factor '(4 + -7r)' equal to zero and attempt to solve: Simplifying 4 + -7r = 0 Solving 4 + -7r = 0 Move all terms containing r to the left, all other terms to the right. Add '-4' to each side of the equation. 4 + -4 + -7r = 0 + -4 Combine like terms: 4 + -4 = 0 0 + -7r = 0 + -4 -7r = 0 + -4 Combine like terms: 0 + -4 = -4 -7r = -4 Divide each side by '-7'. r = 0.5714285714 Simplifying r = 0.5714285714

Solution

r = {-1.333333333, 0.5714285714}

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