What is a solution to (x-3)(x+9)=-27

-6

0

Step-by-step explanation:

By observation we can see one solution is x=0 since this will give us

(0-3)(0+9)=(-3)(9)=-27 which is the result on the right hand side.

Now this is a quadratic equation so it should have another solution. This one doesn't seem as obvious to me.

The goal normally is to get 0 on side and factor if possible or use quadratic formula.  There is also completing the square.

So I'm going to multiply (x-3)(x+9) using foil.

First: x(x)=x^2

Outer: x(9)=9x

Inner: -3(x)=-3x

Last: -3(9)=-27

Combine like terms:

x^2+6x-27

So the equation is:

x^2+6x-27=-27

Add 27 on both sides:

x^2+6x+0=0

x^2+6x=0

Factor x out:

x(x+6)=0

In order for these equation to be true one of the left hand factors need to be 0.

Let's find when x is 0, well that is when x=0.

Let's find when x+6 is 0.

x+6=0 can be solved by subtracting 6 on both sides:

x=-6

The solutions are -6 and 0.

We already checked x=0.

Let's check x=-6:

Plugging in -6 where x is in the given equation:

(-6-3)(-6+9)

(-9)(3)

-27 which is the same as right hand side.

answer:   35 % is the probability of a late departure or an early arrival.

step-by-step explanation:

let l represents the late departure and e represents the early departure.

then, according to the question,

p(l) = 12 %,   p(e) = 27 % and = 4 %

and, we have to find out,

but, we know that,

which is the required equation that will use to find the probability of a late departure or an early departure.

therefore,   the probability of a late departure or an early arrival =   35 %

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.