What is 3,242 round to the nearer ten

would someone be able to explain to me how to solve these problems? I don't need the solutions, I just need an explanation. I ne

Leni [432]

The first 3 are examples of the difference of 2 squares so you use the identity
a^2 - b^2 = (a + b)(a - b)
x^2 - 49 = 0
so (x + 7)(x - 7) = 0
so either x + 7 = 0 or x - 7 = 0
giving x = -7 and 7.
Number 7 reduces to 3x^2 =12, x^2 = 4 so x = +/- 2
Number 8 take out GCf (d) to give
d(d - 2) = 0 so d = 0 , 2
9 and 10 are more difficult to factor
you use the 'ac' method Google it to get more details
2x^2 - 5x + 2
multiply first coefficient by the constant at the end
that is 2 * 2 = 4
Now we want 2 numbers which when multiplied give + 4 and when added give - 5:- -1 and -4 seem promising so we write the equation as:-

2x^2 - 4x - x + 2 = 0

now factor by grouping
2x(x - 2) - 1(x - 2) = 0

(x - 2) is common so

(2x - 1)(x - 2) = 0
and 2x - 1 = 0 or x - 2 = 0 and now you can find x.

The last example is solved in the same way.

8 0

3 years ago

karen drove 3/4 of a mile in 1/60 of an hour .At this rate,how many miles would she drive in one hour

amid [387]

Answer:

45 miles

Step-by-step explanation:

1/60 of one hour (60 minutes) equates to 1 minute

Karen is driving 3/4 of a mile in 1 minute to multiply 3/4 and 60 to get 45 miles

6 0

2 years ago

Si sumamos cinco unidades al doble de un número el resultado es el mismo que si le sumaramos 7 unidades a dichos números.

vesna_86 [32]

Step-by-step explanation:

Primero tienes que encontrar el número que te encuentres con 5 y con el mismo número lo haces con 7.

3 0

3 years ago

Please help with this question. I would appreciate it!

Veronika [31]

Answer:

Mass of A = 5760 grams

Step-by-step explanation:

Surface area is given, so we can set-up a similarity equation to solve for k, proportionality constant. Here, we will relate both of them through k^2, because they are 2 dimensional (area). Thus

Surface Area of A = k^2 * Surface Area of B

28 = k^2 * 40.32

k^2 = 28/40.32

k^2 = 25/36

k = Sqrt (25/36)

k = 5/6

Now, we want to find mass (1 dimensional quantity), thus we can say:

Mass of A = k * Mass of B

Mass of A = (5/6) * (6912)

Mass of A = 5760 grams

8 0

3 years ago

Read 2 more answers

I GIVEEEEE BRAIMLILSTER

timofeeve [1]

Answer:

$\boxed{\boxed{\pink{\bf \leadsto It \ will \ take \ 5 hours \ to \ travel \ 300 \ miles. }}}$

<h3>Step-by-step explanation:</h3>

According to Question , a plane travels 120 miles in 2 hours. So here we will use unitary method .

$\bf\implies If \ it \ covers \ 120 \ miles \ in \ 2 \ hours \\\\\bf\implies Then \ one \ mile \ will \ be \ covered \ in \ \dfrac{120}{2} hrs \\\\\bf\implies Hence \ 300 \ miles \ will \ be \ covered \ in \ \dfrac{2}{120}\times 300 hrs = \red{5 \ hours }$

<h3>Hence it will cover 300 miles in 5 hours .</h3>

Here it was a case of direct proportion in which if two things are directly proportional to each other. If one thing thing increases then the value of second also increases. Here if the time increases then the distance also increases

5 0

2 years ago