All categories

3 years ago

2x^2+15x=8factor or solve as indicated, show all work.please and thank u!

Mathematics

1 answer:

labwork [276]3 years ago

8 0

Answer: x= -8 or x = 1/2

Step-by-step explanation:

2x^2 + 15x = 8 Subtract 8 from both sides to let the whole equation equal 0

- 8 -8

2x^2 + 15x - 8 = 0 Now find two numbers that if you multiply them, their product will be -16 and their sum will be 15. An example is the numbers 16 and -1. 16 times -1 is -16 and 16 plus -1 is 15.

Rewrite the whole equation in this form,

2x^2 +16x - 1x - 8 = 0 Factor on the left side

2x ( x + 8) -1 (x + 8) = 0 Now factor out x + 8

(x + 8) (2x -1) = 0 Set each expression equal zero, because for the whole expression to equation to 0, either one of them or all of them have to equation zero.

x + 8 = 0 or 2x - 1 = 0

-8 -8 +1 +1

x = - 8 2x = 1

x = 1/2

You might be interested in

How many degrees<br>in 1/20 of a full turn?

Yuki888 [10]

Answer:

18 degerees

Step-by-step explanation: i am 100% sure have a nice day.

3 0

3 years ago

11. Mr Lee bought a second hand car for

Marrrta [24]

Answer :

Depends on the rate compound interest is accrued. See answers.

Step-by-step explanation:

We need the compound interest formula which is:

$A = P (1+\frac{r}{n} )^{nt}$

A = final amount

P = initial principal balance

r = interest rate

n = number of times interest applied per time period

t = number of time periods elapsed

It doesn't say how frequently the interest is compounded, so we will do monthly, quarterly, and yearly.

MONTHLY

So we know the car costs $25,480 and he made a down payment of $10,000. By subtracting the down payment from the purchase price we find the loan amount.

$25,480 - $10,000 = $15,480

P = 15,480

r = 4.75% = .0475

n = 12 (12 months in a year)

t = 2

Plug everything into the compound interest formula.

$A = P (1+\frac{r}{n} )^{nt}$

$A = 15480(1+\frac{.0475}{12})^{12*2}$

$A = 15480(1+\frac{.0475}{12})^{24}$

$A = 15480(1+.00396)^{24}$

$A = 15480(1.00396)^{24}$

$A = 15480*1.0992$

$A = $17016.14$

Mr. Lee paid $17,016.14 when the bill came due at 2 years with interest compounded monthly.

QUARTERLY

P = 15,480

r = 4.75% = .0475

n = 4 (4 quarters in a year)

t = 2

$A = P (1+\frac{r}{n} )^{nt}$

$A = 15480(1+\frac{.0475}{4})^{4*2}$

$A = 15480(1+\frac{.0475}{4})^{8}$

$A = 15480(1+.0119})^{8}$

$A = 15480(1.0119)^{8}$

$A = 15480*1.099$

$A = 15480(1.099)$

$A = 17013.20$

Mr. Lee paid $17,013.20 when the bill came due at 2 years with interest compounded quarterly.

YEARLY

P = 15,480

r = 4.75% = .0475

n = 1

t = 2

$A = P (1+\frac{r}{n} )^{nt}$

$A = 15480(1+\frac{.0475}{1})^{1*2}$

$A = 15480(1+\frac{.0475}{12})^{2}$

$A = 15480(1+.0475})^{2}$

$A = 15480(1.0475)^{2}$

$A = 15480*1.0973$

$A = 16985.53$

Mr. Lee paid $16,985.53 when the bill came due at 2 years with interest compounded yearly.

4 0

3 years ago

What is 25/6 with remainder

Leya [2.2K]

4 remainder 1 because six goes into twenty-five four times which is twenty-four and one more will make twenty five

7 0

3 years ago

Read 2 more answers

Isabelle bought some stationery. 1/3 of them were pencils. 5/8 of the remainder were erasers and the rest were rulers. The cost

kobusy [5.1K]

Answer:

Isabelle spent $52.50 more on Erasers than rulers.

Step-by-step explanation:

Step 1

Find the quantity of each stationery bought in fraction

Let us represent the total fraction of what Isabelle bought as: x

1/3x = quantity of pencils bought

5/8 of the remainder = quantity of erasers bought

The remainder = x - 1/3x = 2/3x

5/8 of 2/3x = 5/8 × 2/3x = 5/12x

Hence, 5/12x = quantity of erasers bought

The rest is rulers

1 - (1/3 + 5/12)

1 - (4 + 5/12)

1 - 9/12

1 - 3/4

= 1/4x

Hence, 1/4 = quantity of rulers bought.

Step 2

We find the number of stationeries that Isabelle bought.

The cost of the stationery is

a Pencil: $1.20

an eraser: $1

a ruler: $0.50.

Total amount spent on stationery = 169.50

We have this equation

1.20 × 1/3x + 1 × 5/12x + 0.50 × 1/4x = 169.50

0.4x + 0.4166666667x + 0.125x =

169.50

0.9416666667x = 169.50

x = 169.50 /0.9416666667

x = 179.99999999

Approximately , the number of stationeries that Isabelle bought = x = 180

Step 3

Find the number and the amount spent on each stationery that Isabelle bought

a) i) Quantity of pencils bought = 1/3 x

x = 180

= 1/3 × 180

= 60 pencils

ii) Amount spent on pencils

If 1 pencil = $1.20

60 pencils =

60 × 1.20 = $72

b) i) Quantity of Erasers bought = 5/12x

x = 180

= 5/12 × 180

= 75 pencils

ii) Amount spent on Eraser

If 1 pencil = $1

75 pencils =

75 × 1 = $75

c) i) Quantity of rulers bought = 1/4 x

x = 180

= 1/4 × 180

= 45 pencils

ii) Amount spent on pencils

If 1 pencil = $0.50

45 pencils =

45 × 0.50 = $22.50

Step 4

We were asked to calculate how much more did she spend on erasers than rulers.

In step 3, the amount spent on Erasers = $75

the amount spent on ruler = $22.5

The difference in the amount spent = $75 - $22.5

= $52.5

Therefore, Isabelle spent $52.50 more on Erasers than rulers.

3 0

3 years ago

What is the volume of a right circular cylinder with a radius of 5cm and a height of 12cm?

Tom [10]

Answer: $V=942.47cm^{3}$

Step-by-step explanation:

1. To solve this problem you must use the following formula for calculate the volume of a right circular cylinder, which is shown below:

$V=\pi*r^{2}*h$

Where r is the radius and h is the height.

2. Now, you must substitute the values given in the problem. Therefore, you obtain the following result:

$V=\pi*(5cm)^{2}*(12cm)$

$V=942.47cm^{3}$

3 0

3 years ago

Read 2 more answers

2x^2+15x=8factor or solve as indicated, show all work.please and thank u!​

2x^2+15x=8factor or solve as indicated, show all work.please and thank u!