2x^2+7x-8=0

Simple and best practice solution for 2x^2+7x-8=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 2x^2+7x-8=0 equation:


Simplifying
2x2 + 7x + -8 = 0

Reorder the terms:
-8 + 7x + 2x2 = 0

Solving
-8 + 7x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
-4 + 3.5x + x2 = 0

Move the constant term to the right:

Add '4' to each side of the equation.
-4 + 3.5x + 4 + x2 = 0 + 4

Reorder the terms:
-4 + 4 + 3.5x + x2 = 0 + 4

Combine like terms: -4 + 4 = 0
0 + 3.5x + x2 = 0 + 4
3.5x + x2 = 0 + 4

Combine like terms: 0 + 4 = 4
3.5x + x2 = 4

The x term is 3.5x.  Take half its coefficient (1.75).
Square it (3.0625) and add it to both sides.

Add '3.0625' to each side of the equation.
3.5x + 3.0625 + x2 = 4 + 3.0625

Reorder the terms:
3.0625 + 3.5x + x2 = 4 + 3.0625

Combine like terms: 4 + 3.0625 = 7.0625
3.0625 + 3.5x + x2 = 7.0625

Factor a perfect square on the left side:
(x + 1.75)(x + 1.75) = 7.0625

Calculate the square root of the right side: 2.657536453

Break this problem into two subproblems by setting 
(x + 1.75) equal to 2.657536453 and -2.657536453.

Subproblem 1

x + 1.75 = 2.657536453 Simplifying x + 1.75 = 2.657536453 Reorder the terms: 1.75 + x = 2.657536453 Solving 1.75 + x = 2.657536453 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.75' to each side of the equation. 1.75 + -1.75 + x = 2.657536453 + -1.75 Combine like terms: 1.75 + -1.75 = 0.00 0.00 + x = 2.657536453 + -1.75 x = 2.657536453 + -1.75 Combine like terms: 2.657536453 + -1.75 = 0.907536453 x = 0.907536453 Simplifying x = 0.907536453

Subproblem 2

x + 1.75 = -2.657536453 Simplifying x + 1.75 = -2.657536453 Reorder the terms: 1.75 + x = -2.657536453 Solving 1.75 + x = -2.657536453 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.75' to each side of the equation. 1.75 + -1.75 + x = -2.657536453 + -1.75 Combine like terms: 1.75 + -1.75 = 0.00 0.00 + x = -2.657536453 + -1.75 x = -2.657536453 + -1.75 Combine like terms: -2.657536453 + -1.75 = -4.407536453 x = -4.407536453 Simplifying x = -4.407536453

Solution

The solution to the problem is based on the solutions from the subproblems. x = {0.907536453, -4.407536453}

See similar equations:

| 2X^4+5X^3-5X^2=0 | | 12(m+3)=4(m+12)+6m | | 0.9x+2.3x=-64 | | 8-15x+7x^2=0 | | 6+2w(w)=216 | | 13(4c-8)=2c-8 | | a+(a-2)=(a+5)-a+3 | | 2/3a=8/9 | | x=-2y+18 | | 36a^2-12ab-8b^2=0 | | 14b^2-9b-18=0 | | 2(2x+9)=-15 | | 5x-2(x+1)=2(x+6) | | B=60*L | | c-16=-2 | | .2y+7.8y=54.6 | | 3+6*4/10+4-18 | | x^2-5x+9580=0 | | 14b^2-23b-30=0 | | 3x+1=3x-3+4 | | 6-9x=879 | | 2z^2+17z+10=0 | | 5=t/6 | | 12(12k+11)=12(2k+12) | | 12x4+9x3-15x2/3x2 | | -3(4x+2)+8x=18 | | (7/x)+(9/x-2) | | 481=(7.6n-11.3n) | | 9x+2y=120 | | 7/x+9/x-2 | | 8(t+9)=24 | | 75=3.8r+3.7r |

Equations solver categories