If it's not what You are looking for type in the equation solver your own equation and let us solve it.
4x^2+13=0
a = 4; b = 0; c = +13;
Δ = b2-4ac
Δ = 02-4·4·13
Δ = -208
Delta is less than zero, so there is no solution for the equation
| x^2+(1/3)x+1=0 | | x^2+1/3x+1=0 | | x2-16=0 | | 5(5x-2)=2(9x=3) | | -15+-1x+6x2)=0 | | -15+-1x+6x2=0 | | 5a^2-10a+1=0 | | 3/4=p+1/4 | | 6x2-x-15=0 | | k(k+4)(k+8)=3k | | 35x^2-26x-48=0 | | 24x^2-3x+1,414=0 | | (x+8)^2=128 | | 40x^2-156x-100=0 | | x^2-0.95x+0.15=0 | | 15p2+13p+2=0 | | |2x-x^2-3|=1 | | 3(5p+9)-4()=3p-1 | | -7x^2+70x-175=0 | | 20x+5x^2-105=0 | | x^2-1,73x+4=0 | | x^2-√3*x+4=0 | | x^2-√3x+4=0 | | x−4=7 | | 7(p-3)-4()=3p-1 | | 9×(x-6)-4×(x+1)=3x | | 1.5xX^2=0 | | (x+2)(x-1)=165 | | 2x(3x-1)-14=8 | | (3x+3)(3x-7)=0 | | 3x-4=1/2 | | -13=-52+15x |