(4x)*(7x+1)=60

Solution for (4x)*(7x+1)=60 equation:

(4x)*(7x+1)=60

We move all terms to the left:

(4x)*(7x+1)-(60)=0

We multiply parentheses

28x^2+4x-60=0

a = 28; b = 4; c = -60;
Δ = b2-4ac
Δ = 42-4·28·(-60)
Δ = 6736
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{6736}=\sqrt{16*421}=\sqrt{16}*\sqrt{421}=4\sqrt{421}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-4\sqrt{421}}{2*28}=\frac{-4-4\sqrt{421}}{56}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+4\sqrt{421}}{2*28}=\frac{-4+4\sqrt{421}}{56}
$