7y^2-70=0

Solution for 7y^2-70=0 equation:

7y^2-70=0

a = 7; b = 0; c = -70;
Δ = b2-4ac
Δ = 02-4·7·(-70)
Δ = 1960
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:

$\sqrt{\Delta}=\sqrt{1960}=\sqrt{196*10}=\sqrt{196}*\sqrt{10}=14\sqrt{10}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-14\sqrt{10}}{2*7}=\frac{0-14\sqrt{10}}{14}
=-\frac{14\sqrt{10}}{14}
=-\sqrt{10}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+14\sqrt{10}}{2*7}=\frac{0+14\sqrt{10}}{14}
=\frac{14\sqrt{10}}{14}
=\sqrt{10}
$