(2.1/3)y-5=16

Solution for (2.1/3)y-5=16 equation:

(2.1/3)y-5=16

We move all terms to the left:

(2.1/3)y-5-(16)=0


Domain of the equation: 3)y!=0

y!=0/1

y!=0

y∈R


We add all the numbers together, and all the variables

(+2.1/3)y-5-16=0

We add all the numbers together, and all the variables

(+2.1/3)y-21=0

We multiply parentheses

2y^2-21=0

a = 2; b = 0; c = -21;
Δ = b2-4ac
Δ = 02-4·2·(-21)
Δ = 168
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{168}=\sqrt{4*42}=\sqrt{4}*\sqrt{42}=2\sqrt{42}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-2\sqrt{42}}{2*2}=\frac{0-2\sqrt{42}}{4}
=-\frac{2\sqrt{42}}{4}
=-\frac{\sqrt{42}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+2\sqrt{42}}{2*2}=\frac{0+2\sqrt{42}}{4}
=\frac{2\sqrt{42}}{4}
=\frac{\sqrt{42}}{2}
$