4x^2+7x-28=0

Simple and best practice solution for 4x^2+7x-28=0 equation. Check how easy it is, and learn it for the future. Our solution is simple, and easy to understand, so don`t hesitate to use it as a solution of your homework.

If it's not what You are looking for type in the equation solver your own equation and let us solve it.

Solution for 4x^2+7x-28=0 equation:


Simplifying
4x2 + 7x + -28 = 0

Reorder the terms:
-28 + 7x + 4x2 = 0

Solving
-28 + 7x + 4x2 = 0

Solving for variable 'x'.

Begin completing the square.  Divide all terms by
4 the coefficient of the squared term: 

Divide each side by '4'.
-7 + 1.75x + x2 = 0

Move the constant term to the right:

Add '7' to each side of the equation.
-7 + 1.75x + 7 + x2 = 0 + 7

Reorder the terms:
-7 + 7 + 1.75x + x2 = 0 + 7

Combine like terms: -7 + 7 = 0
0 + 1.75x + x2 = 0 + 7
1.75x + x2 = 0 + 7

Combine like terms: 0 + 7 = 7
1.75x + x2 = 7

The x term is 1.75x.  Take half its coefficient (0.875).
Square it (0.765625) and add it to both sides.

Add '0.765625' to each side of the equation.
1.75x + 0.765625 + x2 = 7 + 0.765625

Reorder the terms:
0.765625 + 1.75x + x2 = 7 + 0.765625

Combine like terms: 7 + 0.765625 = 7.765625
0.765625 + 1.75x + x2 = 7.765625

Factor a perfect square on the left side:
(x + 0.875)(x + 0.875) = 7.765625

Calculate the square root of the right side: 2.786687101

Break this problem into two subproblems by setting 
(x + 0.875) equal to 2.786687101 and -2.786687101.

Subproblem 1

x + 0.875 = 2.786687101 Simplifying x + 0.875 = 2.786687101 Reorder the terms: 0.875 + x = 2.786687101 Solving 0.875 + x = 2.786687101 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.875' to each side of the equation. 0.875 + -0.875 + x = 2.786687101 + -0.875 Combine like terms: 0.875 + -0.875 = 0.000 0.000 + x = 2.786687101 + -0.875 x = 2.786687101 + -0.875 Combine like terms: 2.786687101 + -0.875 = 1.911687101 x = 1.911687101 Simplifying x = 1.911687101

Subproblem 2

x + 0.875 = -2.786687101 Simplifying x + 0.875 = -2.786687101 Reorder the terms: 0.875 + x = -2.786687101 Solving 0.875 + x = -2.786687101 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.875' to each side of the equation. 0.875 + -0.875 + x = -2.786687101 + -0.875 Combine like terms: 0.875 + -0.875 = 0.000 0.000 + x = -2.786687101 + -0.875 x = -2.786687101 + -0.875 Combine like terms: -2.786687101 + -0.875 = -3.661687101 x = -3.661687101 Simplifying x = -3.661687101

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.911687101, -3.661687101}

See similar equations:

| -43x=-0.215 | | 0.16y=0.05 | | 8(x+2)=16x-36 | | y=52x-4 | | 3(x+2)=11x-22 | | 7x^2+4x-28=0 | | sqrt(9t+10)=3t+-6 | | 6+5(x+2)=3(x+6)+2x | | 16y=1/18 | | sqrt(9t+10)=3t-6 | | y=-34x+4 | | 7(x-2)=-9(x+4)+44 | | 6(x^2)=3200 | | 5y-42=2y-61 | | 2/7=-2/3u-1/2 | | y=-23x+4 | | 36v^3-1v=0 | | y=100000x-7+5 | | 2+5x=-3x+74 | | 5/9(8=c)=-20 | | 7x^2+8x+112=0 | | y=-73x+4 | | 2-3+6=10x-x | | x^2-100x+1400=0 | | 8x^2+7x+112=0 | | A(30)=4700(1/2)^(30/14) | | x(x+1)=110 | | 5(cosine(4x))=4 | | 5cos(4x)=4 | | 16+96-3=22 | | (4x/9y)/(2xy/3y^4) | | -b^2-2b+1=0 |

Equations solver categories