Question

1) Solve : x2 + 8x - 48 =0​

Answer 1

Answer:

Step-by-step explanation:

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

+

8

−

4

8

=

0

x^{2}+8x-48=0

x2+8x−48=0

=

1

a={\color{#c92786}{1}}

a=1

=

8

b={\color{#e8710a}{8}}

b=8

=

−

4

8

c={\color{#129eaf}{-48}}

c=−48

=

−

8

±

8

2

−

4

⋅

1

(

−

4

8

)

√

2

⋅

1

2

Simplify

Evaluate the exponent

Multiply the numbers

Add the numbers

Evaluate the square root

Multiply the numbers

=

−

8

±

1

6

2

3

Separate the equations

To solve for the unknown variable, separate into two equations: one with a plus and the other with a minus.

=

−

8

+

1

6

2

=

−

8

−

1

6

2

4

Solve

Rearrange and isolate the variable to find each solution

=

4

=

−

1

2

Solution

=

4

=

−

1

2

Answer 2

Answer:

${x}^{2} + 8x - 48 = 0$

${x}^{2} + (12 - 4)x - 12 \times 4 = 0$

${x}^{2} + 12x - 4x - 12 \times 4 = 0$

$x(x + 12) - 4(x + 12) = 0$

$(x + 12)(x - 4) = 0$

$x + 12 = 0 \\ x = - 12$

$x - 4 = 0 \\ x = 4$