All categories

3 years ago

Need help with homework please

Mathematics

1 answer:

torisob [31]3 years ago

7 0

4. (9x^2 + 13x) + (4x^2 - 8x)

(9x^2 + 13x)

9x^2 = 81 x + 13 x = 94x

(4x^2 - 8x)

4x^2 = 16x - 8x = 8x

94x + 8x = 102x

The answer is 102x

5. (x^2 + 4x + 6) + (x^2 + 8x + 3)

(x^2 + 4x + 6)

4x + 6 = 10x

10x + x^2 = 10x^2

(x^2 + 8x + 3)

8x + 3 = 11x

x^2 + 11x = 11x^2

The answer i 11x^2

6. (-3x^2 + 2x - 8) + (x^2 + 4x)

(-3^2 + 2x + 8)

-3^2 = 9

2x + 8 = 10x

10x + 9 = 19x

(x^2 + 4x)

x^2 + 4x = 4x^2

19x + 4x^2 = 23x^2

The answer is 23x^2.

You might be interested in

the height of a triangle is 4 meters less than the base. if the area of the triangle is 6 m^2 what is the height of the triangle

inna [77]

Answer:

$2m$

Step-by-step explanation:

Alrighty let's do this.

We know that formula for the Area of a triangle is:

$A = \frac{1}{2}bh$

They give us the area as $6m^2$ , so let's include it in the equation.

$6 = \frac{1}{2}bh$

Now we reach a stage where we have 2 unknown variables! That means we can't solve it in its current state. So the idea you should have in cases like these where you have 2 or more unknown variables is, "Can I represent this one variable in terms of another variable?" In this case you can do exactly that. You can represent height in terms of length of the base. We are told the height of the triangle is 4 meters less than the base. That is telling us that $h = b-4$

So replace $h$ in the equation with $b-4$ .

You will now get:

$6 = \frac{1}{2}b(b-4)$

Now we can work towards solving. Let's get simplifying.

$12 = b(b-4)\\12 = b^2 - 4b\\$

bring everything to one side so we can make a quadratic and factor:

$0 = b^2 - 4b - 12\\0 = (b-6)(b+2)\\\\b = 6\\b\neq -2$

We get that $b=6$ .

Since we need the height of the triangle we'll need to call back on what h is. We found earlier that $h = b - 4$ , so to find h, we just sub in our b value into that.

$h = (6) - 4 = 2$

We find that $h=2$

7 0

1 year ago

PLEASE HELP!!!

NemiM [27]

Answer:

D. 2 3 • 3 2 • 5

Step-by-step explanation:

ig I need at least 20 characters to submit my answer. :)

8 0

3 years ago

Graph y=(x+2)^2-3 <br> Show Vertex

nikklg [1K]

$\bf ~~~~~~\textit{parabola vertex form}
\\\\
\begin{array}{llll}
\boxed{y=a(x- h)^2+ k}\\\\
x=a(y- k)^2+ h
\end{array}
\qquad\qquad
vertex~~(\stackrel{}{ h},\stackrel{}{ k})\\\\
-------------------------------\\\\
y=(x+2)^2-3\implies y=\stackrel{a}{1}[x-\stackrel{h}{(-2)}]^2\stackrel{k}{-3}\quad 
\begin{cases}
h=-2\\
k=-3
\end{cases}$

3 0

2 years ago

Please help I'll give brainliest

Liula [17]

the answer is going to be 6.0

Step-by-step explanation:

1.5 + 1.5 = 3

3 + 3 = 6

6 0

3 years ago

The cost of petrol rises by 2 cents a liter. Last week a man bought 20 liters at the old price. This week he bought 10 liters at

In-s [12.5K]

Answer: the old price for 1 liter is $0.3

Step-by-step explanation:

Let x represent the old price for 1 liter of petrol.

Last week a man bought 20 liters at the old price. This means that the total amount that the man paid for 20 liters is 20x.

The cost of petrol rises by 2 cents a liter. This means that the new price per liter is x + 2/100 = x + 0.02

This week he bought 10 liters at the new price. This means that the total amount that the man paid for 10 liters is

10(x + 0.02)

= 10x + 0.2

Altogether, the petrol costs $9.20. This means that

20x + 10x + 0.2 = 9.2

30x + 0.2 = 9.2

30x = 9.2 - 0.2

30x = 9

x = 9/30

x = 0.3

3 0

3 years ago