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2 years ago

Solve the equation f(x)=x3+2x2+4x+8 given that one of its roots is x=−2.

1 answer:

4 0

Okay, first you need to understand that function of x, (or f(x)) is y.

We now plug in x.

f(-2) or y=-2(3)+(2•2)+4(-2)+8
f(-2)=-6+4+-8+8

f(-2)=-2

When x=-2, y=-2. Lets plug it back in to see if its true.

-2=-2(3) + (2x2) + (4(-2)) + 8

-2 = -6 + 4 + -8 + 8

-2 = -2.

Heart if it helps, comment if you need help.

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The difference between two positive integers is 3. If the smaller is added to the square of the larger, the sum is 87.

Komok [63]

Let x be larger integer so x-3 is the smaller
so x^2+ x-3 = 87
x^2 +x -90=0 and factor
(x-9)(x+10)=0
x=9 or x=-10 but x must be positive
so x=9 and smaller number is 6

6 0

3 years ago

Angela drew 9 rhombuses and 6 trapezoids. She wants to find q, the total number of angles in her quadrilaterals. Explain how Ang

Reil [10]

Both rhombuses and trapezoids have 4 angles. Angela can add 9 and 6 which will give her 15 and multiply by 4 which will give her 60.

Angela has 60 angles.

I hope this helped!!! :)

5 0

3 years ago

Solve the equation for y.<br><br> 8x – 9y = 11

SVETLANKA909090 [29]

8x-9y=11

Add 9y to both sides

8x = 11 + 9y

Subtract 11 on both sides

8x - 11 = 9y

Divide 9 on both sides

$\boxed{y = \frac{8x-11}{9} }$

5 0

4 years ago

Please someone help!! I tried my best to complete this problem but i'm stuck now (also am i even doing it right so far??!);(

Alik [6]

Answer and Step-by-step explanation:

You got everything correct so far except for #4.

4. Yes, it is 1. But it would be in months.

So you would put:

1 month = x

12 months = 1 year.

Since the population increases by 1.5 times a <em>month.</em>

For question number 3.

The equation should be:

$f(x) = 100(1.5)^x$ <- Function

$f(x) = 100(1.5)^{12}$ <- Function when x is 12 months (1 year)

(Put those both the same way I put it.)

It gives you the equation to work with, you just have to plug in the values.

1.5 is in the parenthesis because it needs to be the one that is raised by an exponent.

100 is the initial population, so it stays on the outside.

x is the exponent

7 0

3 years ago

The product of two consecutive odd intergers is 1 less than four times thier sum. Find the two integers.

seraphim [82]

Consecutive odd integers are 2 apart
they are x and x+2
the product (x times (x+2)) is 1 less than 4 times their sum

x(x+2)=-1+4(x+x+2)
$x^2+2x=-1+4(2x+2)$
$x^2+2x=-1+8x+8$
$x^2+2x=8x+7 minus (8x+7) from both sides [tex]x^2-6x-7=0$
factor
what numbers multliply to get -7 and add to get -6?
-7 and 1
(x-7)(x+1)=0
set equal to 0
x-7=0
x=7

x+1=0
x=-1

so the x can be 7 or -1
the other number (x+2) can be 7 or 1

test each

7 and 9
7(9)=-1+4(7+9)
63=-1+4(16)
63=-1+64
63=63
true

-1 and 1
-1(1)=-1+4(-1+1)
-1=-1+4(0)
-1=-1+0
-1=-1
true

the 2 integers can be 7 and 9 or -1 and 1 (both pairs of numbers work)

3 0

3 years ago