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5x-25+2x²=17+13x​

5x-25+2x²=17+13x​ equation

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Numerical solution:

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The solution

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5*x - 25 + 2*x  = 17 + 13*x
2x2+5x25=13x+172 x^{2} + 5 x - 25 = 13 x + 17
Detail solution
Move right part of the equation to
left part with negative sign.

The equation is transformed from
2x2+5x25=13x+172 x^{2} + 5 x - 25 = 13 x + 17
to
(13x17)+(2x2+5x25)=0\left(- 13 x - 17\right) + \left(2 x^{2} + 5 x - 25\right) = 0
This equation is of the form
a x2+b x+c=0a\ x^2 + b\ x + c = 0
A quadratic equation can be solved using the discriminant
The roots of the quadratic equation:
x1=Db2ax_{1} = \frac{\sqrt{D} - b}{2 a}
x2=Db2ax_{2} = \frac{- \sqrt{D} - b}{2 a}
where D=b24acD = b^2 - 4 a c is the discriminant.
Because
a=2a = 2
b=8b = -8
c=42c = -42
, then
D=b24 a c=D = b^2 - 4\ a\ c =
(8)224(42)=400\left(-8\right)^{2} - 2 \cdot 4 \left(-42\right) = 400
Because D > 0, then the equation has two roots.
x1=(b+D)2ax_1 = \frac{(-b + \sqrt{D})}{2 a}
x2=(bD)2ax_2 = \frac{(-b - \sqrt{D})}{2 a}
or
x1=7x_{1} = 7
Simplify
x2=3x_{2} = -3
Simplify
Vieta's Theorem
rewrite the equation
2x2+5x25=13x+172 x^{2} + 5 x - 25 = 13 x + 17
of
ax2+bx+c=0a x^{2} + b x + c = 0
as reduced quadratic equation
x2+bxa+ca=0x^{2} + \frac{b x}{a} + \frac{c}{a} = 0
x24x21=0x^{2} - 4 x - 21 = 0
px+x2+q=0p x + x^{2} + q = 0
where
p=bap = \frac{b}{a}
p=4p = -4
q=caq = \frac{c}{a}
q=21q = -21
Vieta Formulas
x1+x2=px_{1} + x_{2} = - p
x1x2=qx_{1} x_{2} = q
x1+x2=4x_{1} + x_{2} = 4
x1x2=21x_{1} x_{2} = -21
The graph
-12.5-10.0-7.5-5.0-2.50.02.55.07.510.012.515.0-200200
Rapid solution [src]
x_1 = -3
x1=3x_{1} = -3
x_2 = 7
x2=7x_{2} = 7
Sum and product of roots [src]
sum
-3 + 7
(3)+(7)\left(-3\right) + \left(7\right)
=
4
44
product
-3 * 7
(3)(7)\left(-3\right) * \left(7\right)
=
-21
21-21
Numerical answer [src]
x1 = 7.0
x2 = -3.0
x2 = -3.0
The graph
5x-25+2x²=17+13x​ equation