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3 years ago

Which of the following is a factor of 2x^2–7x–15 2x–3 x–5 2x–5 x–3

Mathematics

1 answer:

Andreas93 [3]3 years ago

4 0

double bracket factorisation

2 × 15 = 30

find two factors of 30 that add to give -7

(-10, +3)

2x^2 -10x + 3x - 15

2x(x-5) + 3 (x-5)

(2x+3) (x-5)

THE ANSWER IS X-5

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A soccer team won only 10 of their first 30 games. How many of their remaining 20 games will they have to win to have a .500 rec

jeka94

Answer: 5 games

Step-by-step explanation: A .500 record means that the soccer team won half of their games ( that's how I interpret it). Since they are going to play 30 games, they need to win half of 30 or 15 games to have that record. 15-10 = 5. So, they need to win 5 more games to have a .500 record.

8 0

1 year ago

Graph the function.

RideAnS [48]

Answer:

$\displaystyle{y=-3x-1}$

Step-by-step explanation:

I have two methods: standard-learning which will explain overall mathematically - basically formula, etc. - while the other one trick-tips method will rely on choices rather mathematical calculations but with explanation on why and how.

<h3>Standard-Learning</h3>

First, let’s pick two points that are integers since they are easily to be found via graphs. We see that (-1,2) and (0,-1) is a part of the graph so now we finally have picked two points for our calculations.

When we have finally picked two points, we will be using them for slope calculation. This part is crucial for finding an equation of a line because a line has to contain slope in its equation.

To calculate the slope, we use rise over run formula which is:

$\displaystyle{\dfrac{\Delta y}{\Delta x} = \dfrac{y_2-y_1}{x_2-x_1}}$

Note that $\displaystyle{\Delta}$ is delta - in both mathematic and physics, it means changes in.

So, we will be using those two points that we have picked to substitute in the slope formula. Let’s determine that $\displaystyle{(x_2,y_2)=(-1,2)}$ and $\displaystyle{(x_1,y_1)=(0,-1)}$ .

Therefore, our slope will be:

$\displaystyle{m=\dfrac{2-(-1)}{-1-0}}\\\\\displaystyle{m=\dfrac{2+1}{-1}}\\\\\displaystyle{m=-3}$

Next, find the y-intercept. From the graph, we see that the graph intercepts at (0,-1) which is y-intercept so we will only use y-value. Hence, b = -1.

From the slope-intercept form:

$\displaystyle{y=mx+b}$

Substitute m (slope) = -3 and b (y-intercept) = -1. Hence, the equation of line is:

$\displaystyle{y=-3x-1}$

<h3>Fast Way (Trick-Tips)</h3>

Relying on choices and knowledge of graph, notice that there are slopes of 3 and -3.

Keep in mind that if slope is negative, it will decrease down and if slope is positive, it will increase up.

Therefore, cut off all choices with positive slopes which are 1 and 3. We are now left with 2 and 4.

Next, look at the graph and tell its y-intercept. It intercepts y at y = -1 so we take value of -1.

So choice 4 is cut off and now we have choice 2 as the answer.

Learn More:

brainly.com/question/27514958 - Find the line equation with given points

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2 years ago

Find the percent change from the first value to the second 50;31

tiny-mole [99]

Answer:

-0.38%

Step-by-step explanation:

Divide 31 by 50. 31 / 50 = 0.62.

1 - 0.62 = 0.38

Since it is a decrease in change the percent change is negative.

-0.38%

6 0

2 years ago

"What is the name of the relationship between angle 1, and angle 4?

zvonat [6]

1 and 4,2 and 3 are the alternate interior angles

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to analyze the test scores of students in a math class, would a teacher use a dot plot or histogram to represent the scores? bri

frutty [35]

A bar graph would be a better choice because it is able to show how often he/she has gotten a good score.

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3 years ago

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