Please help me !!!!! :(((((

What are the coordinates of the x-intercepts of the parabola y = x² - 8x + 15?

tamaranim1 [39]

Answer:

(3, 0) and (5, 0)

Step-by-step explanation:

we have

$y=x^{2}-8x+15$

we know that

The x-intercepts are the values of x when the value of y is equal to zero

so

For y=0

$x^{2}-8x+15=0$

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$x^{2}-8x+15=0$

so

$a=1\\b=-8\\c=15$

substitute in the formula

$x=\frac{-(-8)\pm\sqrt{-8^{2}-4(1)(15)}} {2(1)}$

$x=\frac{8\pm\sqrt{4}} {2}$

$x=\frac{8\pm2} {2}$

$x=\frac{8+2} {2}=5$

$x=\frac{8-2} {2}=3$

so

x=3, x=5

therefore

The x-intercepts are (3,0) and (5,0)

4 0

2 years ago

Banabas must pay his ex-wife an amount of R350 000 in two years’ time. Calculate the amount that he must invest today to have th

White raven [17]

Answer:

He must invest R297 521 today.

Step-by-step explanation:

The compound interest formula is given by:

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

Where A(t) is the amount of money after t years, P is the principal(the initial sum of money), r is the interest rate(as a decimal value), n is the number of times that interest is compounded per year and t is the time in years for which the money is invested or borrowed.

Banabas must pay his ex-wife an amount of R350 000 in two years’ time.

This means that $t = 2, A(t) = 350000$

Interest rate of 8.15% per annum compounded monthly:

This means that $r = 0.0815, n = 12$ .

Amount he must invest today:

This is P. So

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

$350000= P(1 + \frac{0.0815}{12})^{2*12}$

$P = \frac{350000}{(1 + \frac{0.0815}{12})^{2*12}}$

$P = 297521$

He must invest R297 521 today.

4 0

2 years ago

Please help me with this<br> thanks<br> please let me know if my answer is incorrect

sergey [27]

I just graphed the table next to the graph of g and compared the two.

The y-intercept of f is (0,8) and the y-intercept of g is (0, -2). So f is GREATER THAN the y-intercept of g.

Now to do the average rate of change, I see from the interval [-6,-3] that f is decreasing and for g it is increasing. Thus f is LESS THAN the average rate of change of g.

5 0

2 years ago

The chef has 250 children to feed. If he feeds 50 children an hour, how many children will he still need to feed in 2 hours?

Alborosie

The answer is 100 bc u got to put it into a proportion

7 0

2 years ago

SAM now has 30ml of pop to share equally into glasses.

crimeas [40]

So whole ml's

30 mls
find what 30 is evenly divisble by
factor 30
30=2 times 3 times 5
therefor
30 is divisble by 2,3,5,6,10,15

so he can divide the glass into 2 sevings which is 30/2=15 ml in each

servings ml    fraction
2 15 15/30=1/2
3 10 10/30=1/3
5 6    6/30=1/5
6 5 5/30=1/6
10    3 3/30=1/10
15 2 2/30=1/15

7 0

2 years ago