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3 years ago

Solve equation. X^2-4x-12 = 0

Mathematics

1 answer:

ser-zykov [4K]3 years ago

5 0

Answer:

Step-by-step explanation:

x2 - 4x - 12 = 0

x2 - 6x + 2x - 12= 0

x(x - 6) + 2(x - 6) = 0

x + 2 = 0

x = - 2

x - 6 = 0

x = 6

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If 4 liters equals 1 gallon then how many liters are in15.9 gallon of diluting agent?

svet-max [94.6K]

Answer:

63.6 liters

Step-by-step explanation:

1 gallon = 4 liters

15.9 gallons = ? liters

To find the number of liters, multiply 4 by 15.9.

15.9 gallons = 63.6 liters

If this anser is correct, please make me Brainliest!

4 0

2 years ago

What question is statistical

bagirrra123 [75]

<span>A statistical question is one that can be answered by collecting data and where there will be variability in that data.</span>

3 0

2 years ago

Read 2 more answers

2. Carl needs 15 hours longer than Jennifer to paint a room. If they work together, they can complete the job in 4 hours. Explai

nasty-shy [4]

Answer:

Jennifer would complete the job on her own in 5 hours.

Step-by-step explanation:

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\Delta}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\Delta}}{2*a}$

$\Delta = b^{2} - 4ac$

Rates

The together rate is the sum of their separates rate.

We have that:

Jennifer takes x hours to complete the job on her own, so her rate is 1/x.

Carl needs 15 hours longer than Jennifer, that is, 15 + x hours, so his rate is 1/(15+x).

The together rate is 1/4. So

$\frac{1}{4} = \frac{1}{x} + \frac{1}{15+x}$

$\frac{1}{4} = \frac{15 + x + x}{x(15+x)}$

$\frac{1}{4} = \frac{15 + 2x}{x(15+x)}$

Applying cross multiplication.

$x^2 + 15x = 4(15 + 2x)$

$x^2 + 15x = 60 + 8x$

$x^2 + 7x - 60 = 0$

Quadratic equation with $a = 1, b = 7, c = -60$ . So

$\Delta = 7^{2} - 4*1*60 = 289$

$x_{1} = \frac{-7 + \sqrt{289}}{2} = 5$

$x_{2} = \frac{-7 - \sqrt{289}}{2} = -12$

Since the time to complete the job has to be a positive value.

Jennifer would complete the job on her own in 5 hours.

4 0

2 years ago

The circumference of a circle is about 37.7 cm and the diameter is about 12 cm. What expression best represents the value of π ?

Yakvenalex [24]

Answer:

Step-by-step explanation:

Circumference of a circle means the perimeter of a circle and it is given be

Perimeter=2πr

P=2πr

Though π is a constant

But this question want us to find π

Make π the subject of the formula

Then, divide both side by

π=P/2r

Given that P=37.7cm

And diameter =12

And radius is half of diameter.

Therefore, radius =12/2=6cm

Then

π=P/2r

π=37.7/2×6

π=37.7/12.

Then, the last option is the correct option

6 0

2 years ago

A water tank holds 944 gallons but is leaking at a rate of 5 gallons per week. A second water tank holds 1,180 gallons but is le

podryga [215]

Answer:

Step-by-step explanation:

The equation is

944 - 5x = 1180 - 9x

Notice what is being said. You start with 944 gallons and take off 5 per week

You also start with 1180 gallons and take on 9 per week.

You want to know when the two are equal. The second tank is larger, but it leaks more. That's what's going to bring about equality.

Add 9x to both sides

944 - 5x + 9x = 1180

944 + 4x = 1180

Subtract 944 from both sides.

4x = 1180 - 944

4x = 236

Divide by 4

x = 236/4

x = 59 weeks

8 0

2 years ago