x² + 2x - 5 = 0 factorisation
Answers
Answer:
Use the quadratic formula
=
−
±
2
−
4
√
2
x=\frac{-{\color{#e8710a}{b}} \pm \sqrt{{\color{#e8710a}{b}}^{2}-4{\color{#c92786}{a}}{\color{#129eaf}{c}}}}{2{\color{#c92786}{a}}}
x=2a−b±b2−4ac
Once in standard form, identify a, b and c from the original equation and plug them into the quadratic formula.
2
+
2
−
5
=
0
x^{2}+2x-5=0
x2+2x−5=0
=
1
a={\color{#c92786}{1}}
a=1
=
2
b={\color{#e8710a}{2}}
b=2
=
−
5
c={\color{#129eaf}{-5}}
c=−5
=
−
2
±
2
2
−
4
⋅
1
(
−
5
)
√
2
⋅
1
Answer:
x
2
−
2
x
−
5
=
0
Use the quadratic formula to find the solutions.
−
b
±
√
b
2
−
4
(
a
c
)
2
a
Substitute the values
a
=
1
,
b
=
−
2
, and
c
=
−
5
into the quadratic formula and solve for
x
.
2
±
√
(
−
2
)
2
−
4
⋅
(
1
⋅
−
5
)
2
⋅
1
Simplify.
Tap for more steps...
x
=
1
±
√
6
Simplify the expression to solve for the
+
portion of the
±
.
Tap for more steps...
x
=
1
+
√
6
Simplify the expression to solve for the
−
portion of the
±
.
Tap for more steps...
x
=
1
−
√
6
The final answer is the combination of both solutions.
x
=
1
+
√
6
,
1
−
√
6
The result can be shown in multiple forms.
Exact Form:
x
=
1
+
√
6
,
1
−
√
6
Decimal Form:
x
=
3.44948974
…
,
−
1.44948974
…