All categories

3 years ago

I really need help with my math homework anyone

Mathematics

1 answer:

Art [367]3 years ago

5 0

Answer:

Step-by-step explanation:

First one:

x² + 13x + 15 = 2x + 5

First, combine like terms and place all your results on the left side of this equation: x² + 11x + 10 = 0. Note that (1)(10) = 10 and that 1 + 10 = 11. Thus, this last result factors easily into (x + 1)(x + 10) = 0, so that x + 1 = 1 and x = -1 and also x + 10 = 0 yields x = -10. The solutions (roots, zeros) of the given equation are {-10, -1}.

Second one:

x² = 2x + 63

Again, consolidate all three terms on the left side with "=0" on the right side:

x² - 2x - 63 = 0. Note that 7(-9) = -63 and that -9 + 7 = -2. Thus, in factored form we have (x - 9)(x + 7) = 0, ans so the roots are {-7, 9}.

You might be interested in

One sample has a mean of M= 6, and a second sample has a mean of M = 12. The two samples are combined into a single set of score

lakkis [162]

Answer:

a) 9

b) 10

c) 8

Step-by-step explanation:

We are given the following in he question:

Mean of sample A = 6

Mean of sample B = 12

Formula:

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

$\dfrac{\displaystyle\sum x_a}{n_a} = 6\\\\\dfrac{\displaystyle\sum x_b}{n_b} = 12$

a) original samples have n = 4 scores

$\dfrac{\displaystyle\sum x_a}{4} = 6,\sum x_a = 24\\\\\dfrac{\displaystyle\sum x_b}{4} = 12,\sum x_b = 48\\\\\text{Combined mean} = \displaystyle\frac{\sum x_a + \sum x_b}{4+4}=\frac{24 + 48}{4 + 4} = 9$

b) first sample has n = 3 and the second sample has n = 6

$\dfrac{\displaystyle\sum x_a}{3} = 6,\sum x_a = 18\\\\\dfrac{\displaystyle\sum x_b}{6} = 12,\sum x_b = 72\\\\\text{Combined mean} = \displaystyle\frac{\sum x_a + \sum x_b}{3+6}=\frac{18+72}{3+6} = 10$

c) first sample has n = 6 and the second sample has n = 3

$\dfrac{\displaystyle\sum x_a}{6} = 6,\sum x_a = 36\\\\\dfrac{\displaystyle\sum x_b}{3} = 12,\sum x_b = 36\\\\\text{Combined mean} = \displaystyle\frac{\sum x_a + \sum x_b}{6+3}=\frac{36+36}{6+3} = 8$

7 0

3 years ago

For example, a bag of Vigoro Ultra Turf fertilizer contains 29 pounds of nitrogen, 3 pounds of phosphoric acid, and 4 pounds of

IRINA_888 [86]

When we are given information on different products and are asked to calculate a result from these, we are generally being provided with equations, in this case to calculate the number of bags required to make the requested mixture we have the following equations:

$29A+18B=181\\3A+25B=65\\4A+6B=32$

Where A and B represent the number of bosas of each fertilizer brand, as we have two unknowns we will use two equations like this:

$1) 3A+25B=65\\2) 4A+6B=32$

One incognita is cleared depending on the other

$2) 4A+6B=32\\4A=32-6B\\A=8-\frac{6}{4} B$

The values obtained in the second are replaced

$1) 3A+25B=65\\3(8-\frac{6}{4} B)+25B=65\\24-\frac{18}{4} B+25B=65\\B(-\frac{18}{4}+\frac{100}{4})=41\\B(\frac{82}{4})=41\\B(\frac{41}{2})=41\\B=2$

With the value of B it is replaced in the first one to obtain the value of A:

$A=8-\frac{6}{4} B\\A=8-\frac{12}{4}\\A=8-3\\A=5$

Answer

5 bags of Vigoro Ultra Turf and 2 of Parker's Premium Starter are needed

5 0

3 years ago

What’s the correct answer for this ?<br> The traffic light is approximately _____ feet tall

wlad13 [49]

Answer:

Height = 21.78 ft

Step-by-step explanation:

Tan θ = opposite / Adjacent

tan 40 = opposite / 20

where opposite is the part of the traffic light

0.839 × 20 = opposite

opposite = 16.78 ft

Now the total height of traffic light = 16.78 ft +5 ft

Total Height = 21.78 ft

8 0

3 years ago

each of the letters of the word ALABAMA is written on a piece of paper and then put into a bag. A piece of paper is drawn at ran

Yanka [14]

Answer:

P(A) = 0.57 (to the nearest hundredth)

Step-by-step explanation:

There are 7 letters in total

4 of them are the letter A

⇒ P(A) = 4/7

= 0.5714285714...

= 0.57 (to the nearest hundredth)

5 0

3 years ago

12 workers build a wall in 10 hours.How long does 5 workers build a wall?

Basile [38]

Answer:

5 hours

Step-by-step explanation:

Each person works at a rate 1/100 of wall completed per hour.So five men working at the rate would be 5/100. So, it would...

6 0

2 years ago