Question

Use the quadratic formula to solve the equation if necessary round to the nearest hundredth x^2+x-30=8

Answer 1

-6.18

Explanation:

First we need to get this into an equation form that will allow us to factor it.

x^2+cx+c

Make one side of the equation equal to zero.

x^2+x-30=8

-8 -8

x^2+x-38=0

We can't use the zero product property because it is impossible to multiply numbers to get -38 and the same numbers at to 1. Therefore, let's use the quadratic formula. y=-b√b^2-4(a)(c) /2a

Then, identify your a, b and c. A=your squared number, B= your number neing multiplied by a varable (1x or x), and C is your whole number.

a=1

b=1

c=-38

y=-1√1^2-4(1)(-38) /2(1)

Simplify

y=-1√1+152 /2

y=-1√153 /2

y=-3√17/2

Decimal form: −6.18465843

About -6.18 is your answer.

Hope I helped!

Answer 2

5.68 and -6.68

Explanation:

Use the quadratic formula.

x = (-b+-sqrt(b^2-4ac))/2a

Now let's find the values of a b and c.

Use the standard form of the quadratic equation.

ax^2+bx+c = 0

Using this we can find the values of a b and c.

a = 1

b = 1

c = -30-8

c = -38

Now plug in the values.

We get,

(-1+-3sqrt(17))/2

Which rounded to the nearest hundredth is about,

5.68 and -6.68