(3y-1)(4y+7)=90

Simple and best practice solution for (3y-1)(4y+7)=90 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 (3y-1)(4y+7)=90 equation:


Simplifying
(3y + -1)(4y + 7) = 90

Reorder the terms:
(-1 + 3y)(4y + 7) = 90

Reorder the terms:
(-1 + 3y)(7 + 4y) = 90

Multiply (-1 + 3y) * (7 + 4y)
(-1(7 + 4y) + 3y * (7 + 4y)) = 90
((7 * -1 + 4y * -1) + 3y * (7 + 4y)) = 90
((-7 + -4y) + 3y * (7 + 4y)) = 90
(-7 + -4y + (7 * 3y + 4y * 3y)) = 90
(-7 + -4y + (21y + 12y2)) = 90

Combine like terms: -4y + 21y = 17y
(-7 + 17y + 12y2) = 90

Solving
-7 + 17y + 12y2 = 90

Solving for variable 'y'.

Reorder the terms:
-7 + -90 + 17y + 12y2 = 90 + -90

Combine like terms: -7 + -90 = -97
-97 + 17y + 12y2 = 90 + -90

Combine like terms: 90 + -90 = 0
-97 + 17y + 12y2 = 0

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

Divide each side by '12'.
-8.083333333 + 1.416666667y + y2 = 0

Move the constant term to the right:

Add '8.083333333' to each side of the equation.
-8.083333333 + 1.416666667y + 8.083333333 + y2 = 0 + 8.083333333

Reorder the terms:
-8.083333333 + 8.083333333 + 1.416666667y + y2 = 0 + 8.083333333

Combine like terms: -8.083333333 + 8.083333333 = 0.000000000
0.000000000 + 1.416666667y + y2 = 0 + 8.083333333
1.416666667y + y2 = 0 + 8.083333333

Combine like terms: 0 + 8.083333333 = 8.083333333
1.416666667y + y2 = 8.083333333

The y term is 1.416666667y.  Take half its coefficient (0.7083333335).
Square it (0.5017361113) and add it to both sides.

Add '0.5017361113' to each side of the equation.
1.416666667y + 0.5017361113 + y2 = 8.083333333 + 0.5017361113

Reorder the terms:
0.5017361113 + 1.416666667y + y2 = 8.083333333 + 0.5017361113

Combine like terms: 8.083333333 + 0.5017361113 = 8.5850694443
0.5017361113 + 1.416666667y + y2 = 8.5850694443

Factor a perfect square on the left side:
(y + 0.7083333335)(y + 0.7083333335) = 8.5850694443

Calculate the square root of the right side: 2.930028915

Break this problem into two subproblems by setting 
(y + 0.7083333335) equal to 2.930028915 and -2.930028915.

Subproblem 1

y + 0.7083333335 = 2.930028915 Simplifying y + 0.7083333335 = 2.930028915 Reorder the terms: 0.7083333335 + y = 2.930028915 Solving 0.7083333335 + y = 2.930028915 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-0.7083333335' to each side of the equation. 0.7083333335 + -0.7083333335 + y = 2.930028915 + -0.7083333335 Combine like terms: 0.7083333335 + -0.7083333335 = 0.0000000000 0.0000000000 + y = 2.930028915 + -0.7083333335 y = 2.930028915 + -0.7083333335 Combine like terms: 2.930028915 + -0.7083333335 = 2.2216955815 y = 2.2216955815 Simplifying y = 2.2216955815

Subproblem 2

y + 0.7083333335 = -2.930028915 Simplifying y + 0.7083333335 = -2.930028915 Reorder the terms: 0.7083333335 + y = -2.930028915 Solving 0.7083333335 + y = -2.930028915 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-0.7083333335' to each side of the equation. 0.7083333335 + -0.7083333335 + y = -2.930028915 + -0.7083333335 Combine like terms: 0.7083333335 + -0.7083333335 = 0.0000000000 0.0000000000 + y = -2.930028915 + -0.7083333335 y = -2.930028915 + -0.7083333335 Combine like terms: -2.930028915 + -0.7083333335 = -3.6383622485 y = -3.6383622485 Simplifying y = -3.6383622485

Solution

The solution to the problem is based on the solutions from the subproblems. y = {2.2216955815, -3.6383622485}

See similar equations:

| 8(-1.5)+8y= | | 6r-4-17r+11= | | (3y-1)and(4y+7)=90 | | 9f-f= | | 3x+6=3a | | P=e+ni-s | | 6x-15=2y+3 | | 3(x+y)-2y=19 | | 3s+6t=3 | | 0.15(x+40)-0.06(x-50)=14.4 | | -4n-10+17-18n= | | 30x^3+70x^7+60x^8= | | -2(x-4y)+4x=-3x+2y | | 3(5x+8)= | | -5x+2(3x+3)=8 | | 12c+42d= | | 3(x+y)-2x=19 | | 3p-8=p+2 | | 2j+3=5 | | x+7=-x-7 | | 3(x+y)-2=19 | | 3b+4.72=5b+1.20 | | 3g+5=8 | | 3=7-2n | | 1x+2y=15 | | (44)y-7=73 | | a=18b | | 144=w+9xw+9 | | 27x-246x+240=0 | | x*x=216 | | 2x-2(1x+16)=-32 | | (2y+1)(3+y)=0 |

Equations solver categories