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3 years ago

Solve the quadratic equation by factoring: 15x^2+4x-4=0

1 answer:

7 0

We can factor by grouping. To do so, we multiply the leading coefficient with the constant at the end. In other words, a times c (ax^2 + bx + c).

15*-4 = -60

Now we need to split the b term into two pieces that multiply to -60 and add to 4.

-6 and 10 will work.

Now group one part of b with the 15x^2 and the other part with -4.

(15x^2 + 10x) + (-6x - 4)

Now factor both terms.

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

3x+2 is one of our factors and 5x-2 is the other.

(3x+2)(5x-2)=0

Now just find the zeros.

3x+2 = 0
3x = -2
x = -2/3

And

5x-2 = 0
5x = 2
x = 2/5

So the answer is x = -2/3 and x = 2/5

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What can be concluded about the line represented in the table? Check all that apply. x y –6 –7 2 –3 8 0 The slope is 2. The slop

Stels [109]

The first thing we must do for this case is to find the equation of the line.
$y-yo = m (x-xo)
$
We have then:
$m = (y2 - y1) / (x2-x1)

m = (-3 - 0) / (2-8)

m = 1/2$
We choose an ordered pair:
$(xo, yo) = (8, 0)
$
Substituting values:
$y-0 = (1/2) (x-8)

y = (1/2) x - 4$

From here we conclude:

Intersection with y:
We evaluate x = 0 in the function:
$y = (1/2) (0) - 4

y = -4$

Slope of the line:
$m = 1/2
$

Point (-2, -5):
We evaluate the value of x = -2 and the value of y = -5
$-5 = (1/2) (- 2) - 4

-5 = -1 - 4

-5 = - 5$
The equation is satisfied.

Point (8, 0):
It is part of the table, therefore belongs to the line.

Answer:
The slope is 1/2
The y-intercept is -4.
The points (-2, -5) and (8, 0) are also on the line.

7 0

3 years ago

Read 2 more answers

What is 64 mi/hr=? Ft/s please work out so I can see a example

Arlecino [84]

$64\ \frac{mile}{hour}=x\frac{feet}{second}\\\\
Converting\ unites:\\
1\ mile= 5280\ feet\\
1\ hour=\ 3600\ second\\\\
64\frac{mile}{hour}=64*\frac{5280feet}{3600second}=\frac{33792\ feet}{3600\ second}=93,9\frac{feet}{second}$

6 0

3 years ago

1.) You (or your parents) purchase a new car for $19,725.00 plus 4.75% sales tax. The down payment is $2,175.00 and you (or your

Helga [31]

Answer:

$936.94

Step-by-step explanation:

Remember, that because you paid $2,175 up front (down payment), you can borrow $2,175 less from the bank to purchase the car. So first step: Take new car price of $19,725.00 and multiply it by the sales tax percentage ($19,725 * 0.0475) to get $936.94 of tax.

4 0

2 years ago

Given the circle with the diameter of 33 cm find the area of the circle

exis [7]

Answer:

51.81 cm^2

Step-by-step explanation:

Find The Half Of 33 which is 16.5

Use The Formula For Area

A= $\pi$ x r^2

A= 3.14 x 16.5

A= 51.81 cm^2

3 0

2 years ago

FREEEEEEEEEEEEEEEEEEEEEEEE POINTS!!!!!!!!!!!!!

muminat

Bless ur kind soul :o

4 0

3 years ago