3x2 + 2x - 56 = 0
This is a quadratic equation of the form ax + by + c = 0, where a = 3, b = 2, c = -56.
Use the quadratic formula to solve the equation:
x = [-b ± √(b2 - 4ac)]/2a
x = [-2 ± √[(22 - 4(3)(-56)]]/2(3)
x = [-2 ± √(4 + 672)]/6
x = (-2 ± √676)/6
x = (-2 ± 26)/6
x = (-2 + 26)/6 or x = (-2 - 26)/6
x = 24/6 or x = -28/6
x = 4 or x = -14/3 (as a mixed number, x = - 4 2/3)
Thus, the roots of the equation are x = 4 and x = - 14/3.
3x+56 = 2x+4 3x-2x = 4-56 x = -52
85 + 25 - 56 = 54
15x2 + 2x - 56 = 15x2 + 30x - 28x - 56 = 15x(x + 2) - 28(x + 2) = (15x - 28)(x + 2)
(-9 x -8) + (-16) = (72) -16 = 56
x = 7
3x+56 = 2x+4 3x-2x = 4-56 x = -52
56
30 + 50 - 56 + 2306 = 2330
56 + 82 - 9 = 129
85 + 25 - 56 = 54
23 + 56 - 4 = 75
15x2 + 2x - 56 = 15x2 + 30x - 28x - 56 = 15x(x + 2) - 28(x + 2) = (15x - 28)(x + 2)
(7x - 8)(2x - 7)
(-9 x -8) + (-16) = (72) -16 = 56
8060 Source: calculator
x2 + 7x - 56 cannot be factorised.
x = 7